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Showing papers on "Spectrum analyzer published in 1999"


Patent
13 May 1999
TL;DR: A multi-analyte diagnostic system for use with a computer is described in this paper, which includes a flow analyzer including a co-planar light source-optical detector array.
Abstract: A multi-analyte diagnostic system for use with a computer. The diagnostic system includes a flow analyzer including a co-planar light source-optical detector array, the flow analyzer being communicatable with the computer. The diagnostic system also includes a memory medium readable by the computer and storing computer instructions. The instructions include the following steps. A biological sample is run through the flow analyzer. The identity and quantity of at least one analyte of interest in the biological fluid is determined substantially simultaneously to the sample-running step.

244 citations


Journal ArticleDOI
TL;DR: In this paper, a high-speed multichannel ellipsometer with frequency-coupled rotating compensators and a fixed polarizer and analyzer was proposed for real-time Mueller matrix spectroscopy of surface modification and thin-film growth.
Abstract: We describe the design of a high-speed multichannel ellipsometer in the optical configuration PC1r(ω1)SC2r(ω2)A having frequency-coupled rotating compensators (C1r and C2r) and a fixed polarizer and analyzer (P and A) symmetrically placed about the sample (S) on the polarization generation and detection arms of the instrument. For this instrument the frequency-coupled compensators rotate continuously at ω1= 5ω and ω2=3ω, where π/ω is the fundamental optical period. Although the dual rotating-compensator configuration has been proposed and demonstrated earlier, we focus on its extension to real-time Mueller matrix spectroscopy of surface modification and thin-film growth utilizing high-speed multichannel detection with a wide spectral range. The proposed instrument design provides the capability of extracting all 16 elements of the unnormalized Mueller matrix of an evolving sample at 1024 points from 1.5 to 6.5 eV with potential acquisition and repetition times of 0.2 s. Techniques of data acquisition, data reduction, and instrument calibration are described for the general case of arbitrary compensator retardances and polarizer and analyzer angles. We expect that the proposed instrument will have important applications in studies of surfaces and thin films that exhibit anisotropy and inhomogeneity.

148 citations


01 Jan 1999
TL;DR: The research work described in the thesis is situated in a broad technological context and it is explained what vectorial “nonlinear network” analyzers are and why they are needed.
Abstract: The research work described in the thesis is situated in a broad technological context. It is explained what vectorial “nonlinear network” analyzers are and why they are needed. The importance of traceable calibrations is highlighted, in general as well as applied to the vectorial “nonlinear network” analyzer.

108 citations


01 Jan 1999

80 citations


Patent
05 Apr 1999
TL;DR: In this article, a spectrum analyzer is used to collect a table of samples of the noise power versus frequency, which is then input to a computational algorithm which determines free band sets for one or more preferred modulation formats.
Abstract: Provided are methods and apparatuses for quickly and efficiently locating a frequency band for upstream transmission of data in a data communications network system utilizing cable modems. In a preferred embodiment, a cable modem termination system (CMTS) at the headend performs a lookahead in order to determine the noise power spectrum allocated to its upstream channels. Free bands (noise-free bands available for upstream data transmission) may then be determined based on the noise power spectrum and the upstream channel capacity requirements according to a process that is preferably implemented in computer code at the headend. The lookahead is preferably accomplished by using a spectrum analyzer, which is preferably incorporated into the CMTS at the headend, to collect a table of samples of the noise power versus frequency. This table of samples is input to a computational algorithm which determines free band sets for one or more preferred modulation formats rapidly and efficiently in software without the stepping of the upstream receiver frequency as in the blind frequency hop process. Once a band has been located, the CMTS assigns its frequency to an upstream channel and signals the cable modem of the frequency update.

71 citations


Patent
24 Mar 1999
TL;DR: In this paper, a method and apparatus for data management authentication in a clinical analyzer is described, which includes a sensor for receiving a user sample to be measured and a processor for performing predefined test sequence for measuring a predefined parameter value.
Abstract: A method and apparatus are provided for data management authentication in a clinical analyzer. The clinical analyzer includes a sensor for receiving a user sample to be measured and a processor for performing a predefined test sequence for measuring a predefined parameter value. A memory is coupled to the processor for storing predefined parameter data values. An authentication password is associated with each data transmission by the clinical analyzer and read by an associated computer system to validate each data transmission. The authentication password is generated by the clinical analyzer utilizing predetermined information in each data transfer.

68 citations


Patent
19 Apr 1999
TL;DR: The integrated multi-channel analyzer as mentioned in this paper provides coordinated and cooperative triggering and capture of data across multiple channels in a fiber channel network, and allows for distributive control over triggering decisions across multiple analyzer channels, and also allows for multi-level triggering where different conditions may be detected by different analyzers channels.
Abstract: An integrated multi-channel Fiber Channel analyzer provides coordinated and cooperative triggering and capture of data across multiple channels in a Fiber Channel network. The integrated multi-channel analyzer accommodates up to sixteen separate analyzer channels in a single cabinet. Each analyzer channel is comprised of an input port connection to the Fiber Channel network, a trace buffer memory that captures data and logic circuitry that controls the operation of the trace buffer memory in response to a status condition. A high speed status bus is connected to each analyzer channel and propagates the status conditions of each analyzer channel to all other analyzer channels. In this way, the integrated multi-channel analyzer allows for distributive control over triggering decisions across multiple analyzer channels, and also allows for multi-level triggering where different conditions may be detected by different analyzer channels. Analysis of the data captured by the integrated multi-channel analyzer is further enhanced by a processor resident in the cabinet that is connected by a data/control bus to each analyzer channel and by a hardware search engine associated with each trace buffer memory. The resident processor receives high level commands from a remote host processor and sends selected trace data to the remote host computer over an Ethernet connection.

67 citations


Patent
30 Nov 1999
TL;DR: In this article, a channel plan with a corresponding test plan is implemented in connection with a plurality of nodes that communicate signals, where each test plan prescribes measurement of at least one signal parameter, pertaining to one or more nodes as a whole and/or to channels contained within the nodes.
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. Notably, the controller can be configured to compare results from tests with alarm limits, specified in the test plan, to control the spectrum analyzer to perform a failure time spectrum scan when one or more test results exceed one or more alarm limits, and to generate a plot of power amplitude versus frequency over the frequency spectrum of the node at issue.

65 citations


Book
24 Sep 1999
TL;DR: Instrument systems switches in an automated test system instrument system elements modular instruments and software and connectivity for instrumentation: software and instrumentation distributed measurement network connections instrument drivers graphical user interfaces virtual instruments andSoftware defined instruments.
Abstract: Introduction to electronic instruments and measurements: calibration, traceability and standards electrical standards data acquisition transducers analogue to digital conversion signal sources microwave signal sources digital signal processors microprocessors power supplies user interfaces. Current and voltage measurement instruments: voltage, current and resistance instruments oscilloscopes power measurements. Signal and waveform generation instruments: oscillators pulse generators microsignals. Frequency and time measurement instruments: counters precision timers spectrum analyzers. Lightwave test and measurement instruments: lightwave signal sources lightwave signal analyzers lightwave component analyzers optical time domain reflectometers. Circuit element measurement instruments: impedance measuring semiconductor test instruments network analyzers. Digital domain instruments: logic analyzers protocol analyzers bit error rate. Microwave passive devices. Using electronic instruments: impedance considerations electrical inference electrical grounding distributed parameters and component considerations digital interface issues. Instruments in systems: introduction to instrument systems switches in an automated test system instrument system elements modular instruments. Software and connectivity for instrumentation: software and instrumentation distributed measurement network connections instrument drivers graphical user interfaces virtual instruments and software defined instruments. Distributed and networked instrumentation: smart sensors Internet.

59 citations


Patent
04 May 1999
TL;DR: In this article, a three-pair measurement method was proposed to determine the amplitude and phase transmission response of frequency translating devices including a device under test and two test devices using a vector network analyzer and a controller where one of the devices has reciprocal frequency response characteristics.
Abstract: A three-pair measurement method determines the amplitude and phase transmission response of frequency translating devices including a device under test and two test devices using a vector network analyzer and a controller where one of the devices has reciprocal frequency response characteristics. The characterization of single sideband and double sideband devices such as mixers, is preferably performed by combining data from analyzer two-port swept measurements. The measurement method provides a low-pass equivalent transmission response of the devices.

50 citations


Journal ArticleDOI
TL;DR: In this article, a retarding field vacuum probe and an integrated stack of floating electronics for providing output voltages, measuring currents and voltages and transmitting data to a computer were designed and built to measure the energy distribution of ions bombarding radiofrequency biased electrodes in high-density plasma reactors.
Abstract: A compact floating retarding-field ion energy analyzer and the accompanying electronics have been designed and built to measure the energy distribution of ions bombarding radio-frequency (rf) biased electrodes in high-density plasma reactors. The design consists of two main components, a compact retarding field vacuum probe and an integrated stack of floating electronics for providing output voltages, measuring currents and voltages and transmitting data to a computer. The operation and capabilities of the energy analyzer are demonstrated through ion energy distribution measurements conducted on a 4 MHz rf-biased electrostatic chuck in a 13.56 MHz high-density transformer coupled plasma (TCP) reactor. The analyzer is capable of operating while floating on several hundreds of volts of rf bias and at pressures up to 30 mTorr without differential pumping. The effects of pressure (2–30 mTorr), TCP power (500–1500 W), rf-bias power (0–800 W), gas composition, and ion mass on the ion energy distributions are de...

Journal ArticleDOI
TL;DR: In this article, a new kind of electrostatic charged particle analyzer capable of the parallel detection of a large kinetic energy range is described for the simultaneous detection of electrons scattered from surfaces and having energies between tens of eV to greater than 2000 eV.
Abstract: This article describes a new kind of electrostatic charged particle analyzer capable of the parallel detection of a large kinetic energy range The main purpose envisaged is for the simultaneous detection of electrons scattered from surfaces and having energies between a few tens of eV to greater than 2000 eV A prototype has been constructed that approximates a hyperbolic deflection field for the electrons entering an entrance slit It exhibits an energy resolution of a few eV and a collection efficiency of 005% of 2π sr Useful Auger spectra can be acquired in a time of less than 2 s The significant improvement in spectrum acquisition time that this represents offers many possibilities to further Auger and photoelectron spectroscopy

Patent
05 Nov 1999
TL;DR: In this article, the authors present improved systems and methods for verifying accurate test performance of monitoring systems, particularly for point-of-care service, which are provided as kits with instructions for use.
Abstract: The present invention provides improved systems and methods for verifying accurate test performance of monitoring systems, particularly for point-of-care service. Such monitoring systems typically include a test element containing the test reagent(s), and an electronic analyzer device. A blood or other patient sample is applied to the test element, which is introduced to the analyzer. As the reaction proceeds, the analyzer stores the data and outputs the testing result. Accuracy in the result is dependent upon proper functioning of both the test element and the analyzer. The systems of the present invention provide indicators to evaluate the integrity of the test elements and a verification device to evaluate the performance of the analyzer. Such systems may be provided as kits with instructions for use.

Proceedings ArticleDOI
31 Oct 1999
TL;DR: A TM-UWB scanning receiver has been constructed that allows precision measurement of the impulse response of the channel where measurements can be made out to the maximum communications range of the system.
Abstract: Time modulated ultra-wideband (TM-UWB) techniques allow the transmission and fully coherent reception of RF signals with very large fractional bandwidths for a wide variety of important applications. However, traditional instrumentation (e.g., spectrum analyzers) cannot be used at meaningful distances to measure the channel response for such signals. Without such measurements it has been impossible to create channel models except in a few simple cases. Now a TM-UWB scanning receiver has been constructed that allows precision measurement of the impulse response of the channel where measurements can be made out to the maximum communications range of the system. This versatile system not only captures ultra-wideband propagation waveforms, but information on data symbol statistics. The data collected from this measurement instrument can be used to create channel models, guide selection of locking algorithms, characterize noise, analyze error correction techniques, and eventually study geo-ranging capabilities. Preliminary measurement results are presented for an in-building environment. Results include the value of coherent RAKE combining.

Journal ArticleDOI
TL;DR: In this paper, the authors mounted a compact 25 kV mini-Mott spin polarimeter on a commercial high-throughput hemispherical electron analyzer with a double purpose: to maximize the polarization detection and to preserve the original efficiency of the spectrometer in the spin-integrated measurements.
Abstract: We have mounted a compact 25 kV mini-Mott spin polarimeter on a commercial high-throughput hemispherical electron analyzer with a double purpose: to maximize the polarization detection and to preserve the original efficiency of the spectrometer in the spin-integrated measurements. We have thus replaced the 16-anode microchannel-plate detector with a 12-anode microsphere-plate detector in parallel with a Rice University retarding Mott spin polarimeter. Passing from one detection mode to the other is quick and easy. The transfer optics from the analyzer exit slit to the scattering target of the polarimeter allows the full potential of both the electron analyzer and the spin detector to be exploited. The expected effective Sherman function (Seff=0.17) and figure of merit (η0≅1.4×10−4) are found in the spin-resolved mode, and only 25% of the original efficiency is lost in the spin-integrated acquisitions.

Patent
John W. Mates1
29 Jul 1999
TL;DR: An on-chip logic analyzer unit as mentioned in this paper is a programmable logic analyser embedded within an integrated circuit to test a function of the integrated circuit, such as a memory controller.
Abstract: An on-chip logic analyzer unit. An integrated circuit includes a programmable logic analyzer unit embedded within the integrated circuit to test a function of the integrated circuit.

Journal ArticleDOI
TL;DR: In this paper, a new type of optical spectrum analyzer is proposed that features the cascade connection of different arrayed-waveguide gratings (AWGs) with different channel spacings through optical switches.
Abstract: A new type of optical spectrum analyzer is proposed that features the cascade connection of different arrayed-waveguide gratings (AWGs) with different channel spacings through optical switches. The spectral resolution of our system is determined by the narrowest channel spacing and its available channels are ten times the original channels of the AWG with the spacing. We demonstrate the analyzer using 100- and 10-GHz spaced AWGs.

Proceedings ArticleDOI
26 Feb 1999
TL;DR: In this paper, the applicability of the holographic laser notch filter in a dispersive Raman analyzer is discussed and the implications of these issues on instrument configuration and calibration/validation protocol are discussed.
Abstract: Widespread acceptance of Raman spectroscopy in chemical process monitoring requires instrument calibration, which is automated, repeatable, reliable, verifiable, and transferable from instrument to instrument. Key elements to be calibrated in a dispersive Raman analyzer are Raman emission wavelengths, the spectral response of the instrument, and the excitation laser wavelength. Modern Raman instruments are capable of simultaneously monitoring multiple sample points in a process pipeline. In a typical industrial installation, multiple remote probe heads are coupled to a central instrument (laser source, spectrograph, CCD detector and control/software) via fiber optic cables up to hundreds of meters in length. Instruments must self- calibrate and validate without direct access to remote probe head installations. The presence of a holographic laser notch filter in the system presents unique calibration challenges. The implications of these issues on instrument configuration and calibration/ validation protocol are discussed. Candidate wavelength and intensity calibration references are compared. Examples of industrial Raman applications and their requirements on calibration accuracy and precision are given.© (1999) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Patent
Masao Nagano1
14 May 1999
TL;DR: In this article, a frequency analysis method permitting a high rate and a sweep type spectrum analyzer using such frequency analysis methods is provided, where an inverse swept signal is multiplied by each intermediate frequency signal, and a constant frequency component obtained from the results of the multiplications is extracted as a frequency spectrum included in the signal to be measured.
Abstract: There are provided a frequency analysis method permitting a frequency analysis to be performed at a high rate and a sweep type spectrum analyzer using such frequency analysis method. In the case of multiplying a signal to be measured by a main swept frequency signal; extracting the result of the multiplication through an intermediate frequency filter having a predetermined bandwidth to extract frequency components included in the signal to be measured as intermediate frequency signals; and analyzing the frequency components included in the signal to be measured based on the correspondence relation between a power of each of the intermediate frequency signals and a frequency of the main swept frequency signal, an inverse swept signal is multiplied by each intermediate frequency signal, the inverse swept signal being frequency-swept in the reverse direction to the frequency transition direction of the associated intermediate frequency signal, and a constant frequency component obtained from the results of the multiplications is extracted as a frequency spectrum included in the signal to be measured.

Journal ArticleDOI
TL;DR: In this paper, a pulsed nuclear quadrupole resonance (NQR) spectrometer capable of performing a variety of pulsed and swept experiments is described, which features phase locked, superheterodyne detection using a commercial spectrum analyzer and a fully automatic, computer-controlled tuning and matching network.
Abstract: A new, pulsed nuclear quadrupole resonance (NQR) spectrometer capable of performing a variety of pulsed and swept experiments is described. The spectrometer features phase locked, superheterodyne detection using a commercial spectrum analyzer and a fully automatic, computer-controlled tuning and matching network. The tuning and matching network employs stepper motors which turn high power air gap capacitors in a “moving grid” optimization strategy to minimize the reflected power from a directional coupler. In the duplexer circuit, digitally controlled relays are used to switch different lengths of coax cable appropriate for the different radio frequencies. A home-built pulse programmer card controls the timing of radio frequency pulses sent to the probe, while data acquisition and control software is written in Microsoft Quick Basic. Spin-echo acquisition experiments are typically used to acquire the data, although a variety of pulse sequences can be employed. Scan times range from one to several hours depending upon the step resolution and the spectral range required for each experiment. Pure NQR spectra of NaNO2 and 3-aminopyridine are discussed.

Patent
19 May 1999
TL;DR: In this article, a spectrum analyzer including a signal receiving and processing unit, sampling unit, a histogram measuring unit, an arithmetic unit and a display unit is used to measure the amplitude probability distribution (APD) of the output signal.
Abstract: A spectrum analyzer including a signal receiving and processing unit, a sampling unit, a histogram measuring unit, an arithmetic unit and a display unit. The signal receiving and processing unit receives an input signal according to the desired frequency sweep information. The sampling unit samples a signal output from receiving and processing unit, according to a plurality of threshold values and outputs a plurality of output codes corresponding to sample values of the envelope of the input signal. The histogram measuring unit measures a group of histograms corresponding to the output codes produced by the sampling unit. The arithmetic unit calculates the amplitude probability distribution (APD) of the output signal based on the histograms. The display unit displays a band group having a plurality of the ranges calculated by the arithmetic unit as an area in different states.

Patent
19 Mar 1999
TL;DR: In this article, a first mixer (306) shifts a first end (208) of a desired signal frequency bandwidth (206) to an edge (508) of the first filter frequency bandwidth of a first filter (312), where the first filtering frequency bandwidth is greater than the desired signal frequencies (206). Signals within a first undesired frequency spectrum (504) are attenuated by the first mixer.
Abstract: A first mixer (306) shifts a first end (208) of a desired signal frequency bandwidth (206) of a desired signal (202) to an edge (508) of a first filter frequency bandwidth (502) of a first filter (312), wherein the first filter frequency bandwidth (502) is greater than the desired signal frequency bandwidth (206). Signals within a first undesired frequency spectrum (504) are attenuated by the first filter (314). A second mixer (316) shifts a second end (210) of the desired signal frequency bandwidth (206) to an edge (608) of a second filter frequency bandwidth (602) of a second filter (320) to receive the desired signal (202).

Patent
14 Jun 1999
TL;DR: In this article, a spectrum analyzer can be used to produce a first two-dimensional array of time varying spectral analysis image input signals, a reference image generator for producing a second two-dimensions array of spectral analysis reference signals, and a timeintegrative correlator, which can be non-coherent or coherent, or correlating the two groups of image representitive signals to determine the degree of matching between an input image and a library reference image.
Abstract: A spectrum analyzer for producing a first two-dimensional array of time varying spectral analysis image input signals, a reference image generator for producing a second two-dimensional array of spectral analysis image reference signals, and a time-integrative correlator, which can be non-coherent or coherent, or correlating the two groups of image representitive signals to determine the degree of matching between an input image and a library reference image. The spectrum analyzer can include an interferometer, a tunable optical filter, or a time-wavelength-multiplexing holographic lens for viewing the input image. A monolithic non-holographic version provides a rugged, compact and portable image analyzer for examining many types of images.

Patent
14 May 1999
TL;DR: In this paper, a spectrum analyzer is used to determine the light emission characteristics of an authentication mark that is invisible when illuminated with visible light but is visible when illuminated by IR light.
Abstract: A spectrum analyzer determines the light emission characteristics of an authentication mark that is invisible when illuminated with visible light but is visible when illuminated with IR light. The spectrum analyzer includes an IR light source, a mirror positioned to deflect light from the IR light source in a direction that is substantially perpendicular to a surface of the authentication mark, a first lens for collimating light that is emitted by the authentication mark in response to an illumination by the light from the IR light source, an optical element comprising a prism or a hologram for generating a spectrum from the collimated light, a second lens for imaging the spectrum, an IR light blocking filter, a detector positioned to receive light components of the spectrum after the spectrum has been imaged by the second lens and filtered by the IR light blocking filter, and a control unit connected to the detector and programmed to read the authentication mark based on intensities of the light components received by the detector.

Patent
11 Aug 1999
TL;DR: In this article, a test pattern generator applies test patterns repeatedly to the device under test, and a spectrum analyzer unit finds a differential between voltage values occurring between opposite ends of the detection resistor, and voltage values proportional to power supply current values of a device known to perform properly.
Abstract: A tester detects an abnormality in a quiescent power supply current of a device under test. In the tester, a programmable voltage generation source controls a power supply unit, providing a device under test with power. A test pattern generator applies test patterns repeatedly to the device under test. Power supply current to the device under test is converted into voltage values by a detection resistor. A spectrum analyzer unit finds a differential between voltage values occurring between opposite ends of the detection resistor, and voltage values proportional to power supply current values of a device known to perform properly, as measured beforehand. The spectrum analyzer ouputs a power of a fundamental wave of a frequency spectrum obtained by applying the EFT method to the differential. The decision unit prestores spectrum reference values Po as the maximum values for power of the fundamental wave, giving a decision that the quiescent power supply current is abnormal if the power is in excess of the spectrum reference value. The decision is sent out to a CPU, and displayed on a display unit.

Journal ArticleDOI
TL;DR: In this article, the authors proposed an inexpensive rotating analyzer unit, which allows a conventional null type ellipsometer to work as rotating analyzers-fixed analyzer automatic ellipsometers without sacrificing the possibility to work in null mode.
Abstract: The theory and design of an inexpensive rotating analyzer unit is presented, which allows a conventional null type ellipsometer to work as rotating analyzer–fixed analyzer automatic ellipsometer, without sacrificing the possibility to work in null mode The mode switching is performed simply by adding or removing the rotating analyzer from its holder It is shown that the rotating analyzer phase shift in rotating analyzer–fixed analyzer mode can be run-time determined from the measured Fourier coefficients This avoids any need of recalibration procedure after mode switching and makes unnecessary plane of incidence synchronization, which further simplifies the needed hardware and reduces the errors connected with the phase shift instability of the output signal The run-time phase shift calibration procedure and subsequent ellipsometric angles determination do not involve normalization of the output signal Fourier coefficients to the zeroth harmonic, eliminating in this way the influence of the dc compone

Journal ArticleDOI
TL;DR: Several applications such as a miniaturized spectrum analyzer and one-step optical computing units for addition, integration, or differentiation of one-dimensional or two-dimensional optical signals are presented.
Abstract: An efficient method for optically actuating a micromechanical cantilever is presented for the first time to our knowledge. Measurable responses can be obtained for moderate light sources if electron tunneling occurs between the cantilever tip and a metallic contact below it. The small deflection of the cantilever that is due to light pressure is sufficient then to produce large tunneling current variations. On the basis of this effect several applications such as a miniaturized spectrum analyzer and one-step optical computing units for addition, integration, or differentiation of one-dimensional or two-dimensional optical signals are presented.

Patent
26 Mar 1999
TL;DR: In this article, the authors proposed a highly accurate acoustic monitoring device by which it can be judged automatically whether or not the monitoring device is normal by automatically matching the input level of newly sampled acoustic data for monitoring with that of in-advance sampled past reference data even if the condition for sampling acoustic data varies with each other.
Abstract: PROBLEM TO BE SOLVED: To provide a highly accurate acoustic monitoring device by which it can be judged automatically whether or not the monitoring device is normal by automatically matching the input level of newly sampled acoustic data for monitoring with that of in-advance sampled past reference data even if the condition for sampling acoustic data varies with each other. SOLUTION: This acoustic monitoring device is provided with a frequency analyzer 4 to analyze the frequency of digitalized acoustic signal which is issued from an acoustic input device 2 for picking a sound from an object to be monitored, a level correction device 5 to correct the level of the analyzed acoustic data to the specified value, a judging device 8 which compares the corrected acoustic data with the reference data of past acoustic spectrum of the object that is sampled at the specified level in advance and judges whether or not the result is normal, and an indication device 7 to indicate the judgment result.

Patent
08 Jul 1999
TL;DR: In this article, an impulse method was used to measure and detect the degree of degradation of a concrete structure at a deep portion by analyzing the deviation between the resonance frequency spectra from a defectless section and other sections.
Abstract: PROBLEM TO BE SOLVED: To accurately and nondestructively measure and detect the degree of degradation of a concrete structure at a deep portion by analyzing the deviation between the resonance frequency spectra from a defectless section and other sections. SOLUTION: The reference resonance frequency spectrum of the defectless section of a concrete structure 10 to be measured is prepared in advance by measuring the resonance frequency of the section by applying vibrations to the section. Then the resonance frequency spectrum of another measured section is prepared by measuring the resonance frequency of the section by applying vibrations to the section. Then the degree of degradation of the internal portion of the concrete structure 10 is discriminated by analyzing the deviation between both prepared resonance frequency spectra by superposing the spectra upon another. An impulse method in which a prescribed portion is hit with an impact hammer 11, etc., is used as the vibration applying means. The vibration applying force of the hammer 11 and the vibration of the structure 10 are respectively detected by means of a force detecting pickup 16 and an acceleration pickup 16 and the signals of the pickups 12 and 16 are inputted to a high-speed Fourier transformation analyzer 15.

Journal ArticleDOI
TL;DR: This mixed analog-digital system, based on a TMS320C31 Digital Signal Processor (DSP), is implemented in a single board to be hosted in the Personal Computer’s ISA bus and allows for additional features to be performed without the need of external equipment.
Abstract: This paper presents and discusses some applications and advantages of a hybrid spectrometer system that contains a high performance Pulse-Height Analyzer (PHA) and a Digital Pulse Processor (DPP). This mixed analog-digital system, based on a TMS320C31 Digital Signal Processor (DSP), is implemented in a single board to be hosted in the Personal Computer’s ISA bus. Beyond the independent use of the PHA and the DPP units, their integration allow for additional features to be performed without the need of external equipment. Among those features are pileup rejection, pulse shape discrimination, ballistic deficit correction and the capability to measure the experimental noise in order to optimize the pulse shaping parameters or to correct the pulse heights given by the analog PHA.