• Title/Summary/Keyword: signals

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A Few Applications of Polarity Correlation Method in a Frame of Deterministic Signals

  • Kim, io-Sasaki;Mariko Ikeda
    • 제어로봇시스템학회:학술대회논문집
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    • 2002.10a
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    • pp.86.1-86
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    • 2002
  • Polarity correlation is a simplified version of the usual, having a possibility of real-time processing without any reduction of precision. In this paper, its applicability in deterministic signals is first explored generally, by theoretical or numerical analysis of four kinds of the typical signals. Then, based on the results, its two applications are proposed, that are detection and demodulation of FSK signals in digital communication, and time delay estimasion in ultrasonic A-mode measurement. The effectiveness of the proposed applications is confirmed by its superior implementation ability and the results of numerical experiments under practical circumstances.

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On the Mathematical Model for the Statistics of W-CDMA Signals (W-CDMA 신호의 통계적 특성에 대한 수학적 모델에 관한 연구)

  • 정철수;김형진;부수일;김철성
    • Proceedings of the IEEK Conference
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    • 1999.06a
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    • pp.33-36
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    • 1999
  • This paper proposes a mathematical model for the statistics of the W-CDMA signals with different bandwidth. Based on the statistics of numerically generated signals, a mathematical model is obtained such as Rayleigh, Rician, and Maxwell distribution. We employ Chi-square test to verify the fitness of the mathematical model with signal statistics. The results show obviously that the new proposed model is useful for representing W-CDMA signals.

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Perfect Reconstruction in Sub-Nyquist Nonuniform Sampling of Signals with Known upper Time-frequency Boundary (비 균일 표본화 신호의 완전 복구에 관한 연구)

  • 이희영;정현권
    • Proceedings of the IEEK Conference
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    • 2002.06e
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    • pp.9-12
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    • 2002
  • The problem of sub-Nyquist nonuniform sampling for the perfect reconstruction of signals with time-varying spectral contents is studied. The signals are assumed to have a known instantaneous bandwidth in time-frequency domain. As the function of time, the nonuniform sampling pattern of a given signal, that is, the instantaneous sampling frequency is determined by the observation of instantaneous bandwidth based on time-frequency analysis. The proposed sampling pattern guarantees the perfect reconstruction of nonuniform sampled signals under Nyquist-sampling rate in average.

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Machining Characteristics Detection of Endmill Milling Tool (엔드밀 밀링공구의 가공특성검출)

  • 맹민재;조성산;정준기
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 1996.11a
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    • pp.678-682
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    • 1996
  • Acoustic emission(AE) is monitored during end milling with a sensor attached to the cutting fluid discharge nozzle. Cutting forces are also measured and compared with the AE signals to examine the reliability of the AE signals. It is demonstrated that the AE signals provide reliable informations about the cutting processes and tool states. Moreover, edge chipping and fracture of tools can be successfully detected using both the AE signals and cutting forces.

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Optical Signals Using Superposition of Optical Receiver Modes

  • Lee, Jae Seung
    • Current Optics and Photonics
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    • v.1 no.4
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    • pp.308-314
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    • 2017
  • A particular optical receiver has its own optical receiver modes (ORMs) determined by its optical and electrical filters. Superposing the ORM waveforms at the transmitter, we can generate a new type of optical signals, called ORM signals. After optical detection, they produce pre-specified voltage waveforms accurately, which is advantageous for digital signal processing. Assuming a Gaussian optical receiver, where the optical and electrical filters are Gaussian, we illustrate various phase-shift keying ORM signals using two ORMs by changing their relative phase. We also illustrate multi-level ORM signal patterns using two or more ORMs.

Noise Rejection of EMG Signals for the Control of Rehabilitation Robotic Am System (재활 로봇 팔 제어를 위한 근전도 신호의 잡음제거에 관한 연구)

  • 오승환;백승은;나승유;이희영
    • Proceedings of the IEEK Conference
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    • 2001.06e
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    • pp.65-68
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    • 2001
  • In the rehabilitation robotic arm systems for the disabled with spinal code injury, EMG signals are used in the control of the robotic arm. EMG signals are corrupted by many kinds of noises such as ECG signal, power noise and contact noise of electrode. Noise rejection improves the performance of the EMG pattern classification. In this paper, a variable bandwidth filter (VBF) and wavelet transform are used for the noise rejection of EMG signals and the comparison of SNR is given. Also, some statistical characteristics of features are investigated.

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비선형 상관차원 분석을 통한 EEG 뇌파신호 특성 추출

  • Kang, Kun;Lee, Hyoung
    • Journal of Information Technology Applications and Management
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    • v.9 no.4
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    • pp.165-177
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    • 2002
  • For measuring EEG with the international 10-20 electrode system on 16 channels, and to analyze the interrelationship between the original signals and the changed signals after the stimulation, we use the scent of lavender which stimulates the olfactory sense. Moreover, the effect of the scent stimulation to the brain is analyzed. The purpose of this analysis is to apply these results to the computerized mapping of the brain signals and to find possible ways of specifying the source of the brain signals through various medical applications.

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Characteristics of AM and PM Signals in Multi-Carrier Polar Transmitter

  • Kang, Sanggee
    • International journal of advanced smart convergence
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    • v.10 no.4
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    • pp.45-51
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    • 2021
  • Polar transmitter can support multi-band and multi-mode operation. The efficiency of frequency usage can be increased if polar transmitters can transmit multi-carrier signals. In this paper the configuration of polar transmitters is investigated to generate multi-carrier signals. Spectrum and CCDF Simulation results of two-carrier signals generated by the polar transmitter can be used to design of PM and AM path in a polar transmitter.

Species Selective Spectroelectrochemistry Employing Derivative Absorbance Signals

  • Zhang, Chaojiong;Park, Su-Moon
    • Bulletin of the Korean Chemical Society
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    • v.10 no.3
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    • pp.302-308
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    • 1989
  • Species selective spectroelectrochemistry (SSSE) is described by relating the derivative absorbance (dA/dt) signals with electrochemical currents for conventional transient electrochemical experiments. Expressions relating the currents with the dA/dt signals were obtained. From these expressions, physical constants such as coefficients and molar absorptivities of electrogenerated species can be determined. By obtaining both derivative absorbance and current signals concurrently and comparing them, one can perform the SSSE experiments. The utility of the SSSE in sorting out electrochemical information is demonstrated.