• Title/Summary/Keyword: spectrum analyzer

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A Study on the Pulse Doppler System with M-mode Image and Spectrum Analyzer (주파수 해석기와 M-mode 영상을 갖는 펄스 도플러 장치의 개발에 관한 연구)

  • Jeong, Taek-Seob;Park, Sei-Hyun;Kim, Young-Kil
    • Proceedings of the KIEE Conference
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    • 1987.07b
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    • pp.1217-1220
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    • 1987
  • We have developed a Ultra Sound Pulsed Doppler System with two-dimensional M-mode image and Spectrum analyzer. The image of the M-mode is composed of time and depth axes. The Spectrum analyzer shows the spectrum of Doppler signal which represents the velocity component of time dependent blood-flow behavior. The spectrogram using Spectrum analyzer is composed of frequency and amplitude axes. The outputs of the system are audio signals, velocity curves, velocity profiles, M-mode images and spectrogram.

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Pattern Recognition Using Spectrum Analyzer and Neural Network (신경망의 스펙트럼 분석기를 이용한 패턴 인식)

  • 김남익;한수환;전도홍
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • 1996.10a
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    • pp.211-214
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    • 1996
  • This paper propose a method for pattern recogniton using spectrum analyzer and fuzzy ARTMAP. Contour sequences obtained from 2-D planar images represent the Euclidean distance between the centroid and all boundary pixels of the shape, and are related to the overall shape of the images. The Fourier transform of contour sequence and spectrum analyzer are used as a means of feature selection and data reduction. The three dimensional spectral feature vectors are extracted by spectrum analyzer from the FFT spectrum. These Spectral feature vectors are invariant to shape translation, rotation, and scale transformations. The fuzzy ARTMAP neural network which is combined with two fuzzy ART modules is trained and tested with these feature vectors. The experiments include 4 aircrafts and 4 industrial parts recognition process are presented to illustrate the high performance of this proposed method in the ion problems of noisv shapes.

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A Study on the Design and mplementation of Frequency Converter applied to Spectrum Analyzer (스펙트럼 분석기에 적용한 주파수 변환기의 설계 및 구현에 관한 연구)

  • 이진성;송문규;김태회;박영철;차균현
    • Proceedings of the Korean Institute of Communication Sciences Conference
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    • 1991.10a
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    • pp.103-106
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    • 1991
  • Spectrum Analyzer is a useful measure instrument to display the distributed power of electrical signal as a function of frequency. It adopts the superheterodyne receiver, which mixes RF with L0 to output IF. So in this paper, two GHz-order microstrip low-pass filters, 2-section wilkinson power divider, and singly balanced diode mixer have been designed and implemented necessary to make the frequency converter applied to RF spectrum analyzer.

Multi - channel Spectrum Analyzer for High Capacity Optical Transport Networks

  • Youn, Ji-Wook;Kim, Hyung-Joo;Lee, Jong-Hyun
    • Journal of the Optical Society of Korea
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    • v.7 no.4
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    • pp.249-252
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    • 2003
  • A simple multi-channel spectrum analyzer using an InGaAs array sensor and a diffraction grating is proposed and developed for high-capacity optical transport networks. With the developed multichannel spectrum analyzer, we could measure signal power, wavelength, and optical signal-to-noise ratio of each channel for multi-channel optical signals with 100 GHz and 50 GHz channel spacing, simultaneously. We could measure each channel power and wavelength with a deviation of less than 0.2 dB and 0.063 nm, respectively. We have obtained optical signal-to-noise ratio with a deviation of less than 1.0 dB compared with conventional optical spectrum analyzer in the wide input power range between -42 dBm and -27 dBm per channel.

Development of Linux based Real-Time Spectrum Analyzer for Puretone Audiometer (순음청력검사기를 위한 리눅스 기반 실시간 스펙트럼 분석기 개발)

  • Kang, Deok-Hun;Shin, Bum-Joo;Jeon, Gye-Rok;Wang, Soo-Geun
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.12 no.6
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    • pp.2830-2839
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    • 2011
  • Because the puretone audiometer is an important medical instrument used to diagnose hearing loss, the IEC and ANSI has been published a specification with which audiometer should comply. This paper describes development of Linux based real-time spectrum analyzer which is dedicated to puretone audiometer. It can measure not only hearing level but also compliance of IEC standard for puretone audiometer such as frequency accuracy, harmonic distortion, pulsed tone, narrow band noise and linearity. We have verified our real-time spectrum analyzer through comparing to commercial product.

Two Noise Parameter Measurement Methods Using Spectrum Analyzer and Comparison (스펙트럼 분석기를 이용한 2가지 잡음 파라미터 측정방법과 비교)

  • Lee, Dong-Hyun;Yeom, Kyung-Whan
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.26 no.12
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    • pp.1072-1082
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    • 2015
  • In this paper, we propose two noise parameter measurement methods using spectrum analyzer. First method, we measure a noise correlation matrix using the 6-port network, and we calculate noise parameters using measured a noise correlation matrix. Second method, we directly measure noise figures of the DUT for source impedance changes, and then noise parameters are extracted from the measured noise figures. In order to measure a noise figure, we present a method of measuring a noise figure of the DUT that have arbitrary source impedances using spectrum analyzer and a method of eliminating a noise effect of a impedance tuner. Finally, the noise parameters of a passive and active DUT using proposed two methods are compared. The comparison shows that the two results obtained from for the two methods give almost identical noise parameters. The noise parameters measured by 6-port network accurately predict measured noise figures of the DUT for source impedance changes, and noise parameters measured by 6-port network is verified from the comparison.

A Study on the Relationship between Aging and Partial Discharge Characteristics of the Mica/Epoxy Composite Insulation Systems (l) (Mica/Epoxy 복합 절연계통의 부분방전 특성과 열화 관계에 관한 연구(I))

  • Kang, D.S.;Lee, W.Y.;Park, C.H.;Kwak, Y.S.;Kim, K.Y.
    • Proceedings of the KIEE Conference
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    • 1992.07b
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    • pp.976-979
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    • 1992
  • There are lots of problem which are delaminations and partial discharge of insulation materials in high-voltage rotating machines caused by mechanical, electrical and thermal aging. Several experiments have been aiming at finding the useful diagnostic parameters from the partial discharge characteristics by applying a new measurement techniques. This paper deals with the partial discharge characteristics (pulse height, pulse angle, pulse frequency spectrum and time interval), which may be a useful diagnostic concept in predicting insulation condition of mica/epoxy composite insulation materials, by using several measurement equipments (frequency spectrum analyzer. multichannel analyzer and time interval analyzer).

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On-line partial discharge measurement techniques of hydro-generator windings (수력 발전기 권선에서의 운전중 부분방전 측정기법)

  • 황동하;김진봉;김용주;박명수;김택수
    • The Transactions of the Korean Institute of Electrical Engineers
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    • v.45 no.2
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    • pp.294-300
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    • 1996
  • In hydro-generator, a groundwall insulation of stator windings gradually deteriorates due to mechanical, thermal, electrical and environmental stresses. These stresses combine to result in loose windings, delamination of the stator insulation and/or electrical tracking of the endwinding, all of which can lead to stator insulation failures. Conventionally, off-line tests such as partial discharge measurement, DC/AC current and .DELTA.tan.delta. tests has been used for estimation of winding condition. However, off-line test requires large power supply and generator outage. In addition, major cause of insulation problems such as loose wedges and slot dischages may not be found with off-line diagnoses. This paper introduces the on-line partial discharge measurement techniques using frequency spectrum analyzer(FSA) for the generator stator windings. The experimental results from the UIAM #1 hydro-generator confirms a optimistic application of on-line generator diagnosis method as a reliable tool for evaluation of winding condition.

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Support of Automatic Calibration for Computerized Puretone Audiometer Using Linux Real-time Spectrum Analyzer (리눅스 실시간 스펙트럼 분석기를 이용한 컴퓨터 기반 순음청력검사 시스템의 자동 보정 지원)

  • Lee, Seung-Hee;Shin, Bum-Joo;Song, Bok-Deuk;Kim, Jin-Dong;Jeon, Gye-Rok;Wang, Soo-Geon
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.25 no.10
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    • pp.837-843
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    • 2012
  • Compared to conventional pure-tone audiometer(PTA), the computerized one has several advantages such as relatively lower price, better flexibility, and easy operation. In addition, the computerized PTA can be easily extended to support automatic calibration. In this study, the support of automatic calibration in the computerized PTA has been addressed using the Linux realtime spectrum analyzer and network. In terms of accuracy, the new automatic calibration machine was compared to the existing manually operated one. According to the comparison, normal operation and high accuracy were observed within the scope of the international standard.

Noise Reduction Algorithm For The Detection of Fine Ion Signals in Residual Gas Analyzer (잔류가스분석기의 질량 스펙트럼 검출 성능 향상을 위한 잡음제거 알고리즘)

  • Heo, Gyeongyong;Choi, Hun
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.68 no.1
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    • pp.102-107
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    • 2019
  • This paper proposes a method to improve the mass spectral detection performance of the residual gas analyzer. By improving the mode estimation method for setting the threshold value and improving the additive noise elimination method, it is possible to detect mass spectrums having low peak values of the threshold level difficult to distinguish from noise. Ion signal blocks for each mass index with noise removed by the improved method are effective for eliminating invalid ion signals based on the linear and quadratic fittings. The mass spectrum can be obtained from the quadratic fitted curves for the reconstructed ion signal block using only the valid ion signals. In addition, the resolution of the mass spectrum can be improved by correcting the error caused by the shift of the spectral peak position. To verify the performance of the proposed method, computer simulations were performed using real ion signals obtained from the residual gas analysis system under development. The simulation results show that the proposed method is valid.