• 제목/요약/키워드: Interference noise

검색결과 1,345건 처리시간 0.028초

Multidimensional Adaptive Noise Cancellation of Stress ECG Signal

  • Gautam, Alka;Lee, Young-Dong;Chung, Wan-Young
    • 한국정보통신학회:학술대회논문집
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    • 한국해양정보통신학회 2008년도 춘계종합학술대회 A
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    • pp.285-288
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    • 2008
  • In ubiquitous computing environment the biological signal ECG (Electrocardiogram signal) is usually recorded with noise components. Adaptive interference (or noise) canceller do adaptive filtering of the noise reference input to maximally match and subtract out noise or interference from the primary (signal plus noise) input thereby adaptively eliminate unwanted interference from the ECG signal. Measured Stress ECG (or exercise ECG signal) signal have three major noisy component like baseline wander noise, motion artifact noise and EMG (Electro-mayo-cardiogram) noise. These noises are not only distorted signal but also root of incorrect diagnosis while ECG data are analyzed. Motion artifact and EMG noises behave like wide band spectrum signals, and they considerably do overlapping with the ECG spectrum. Here the multidimensional adaptive method used for filtering which is more effective to improve signal to noise ratio.

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도로교통소음저감을 위한 간섭장치 주파수특성에 관한 연구 (The study of frequency characteristic of Interference Device on the noise barrier edge for reduction of Traffic noise)

  • 장강석;윤제원;김영찬;김두훈
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2002년도 춘계학술대회논문집
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    • pp.134-139
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    • 2002
  • We have made known the study of shape development of interference device for vehicle noise control. It's primary object greatly attenuate the noise due to transport vehicle by small products installed on the noise barrier edge. Also, it is able to improve the insertion loss of a noise barrier without increasing the height. The present time, we set up a newly manufactured products on the noise barrier edge and testify to it's the performance make use of an experiment and evaluation for the reduction of highway traffic noise. In this paper the frequency characteristic of interference device of noise barriers with attached newly developed products in terms of shape, absorptive material and split panel, are examined using field test at highway.

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철도소음 저감을 위한 방음벽 상단 간섭효과에 관한 연구 (A Study on the Interference Effect of the Noise Barrier Edge for Railway Noise Reduction)

  • 심상덕;장강석;김영찬;김두훈
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2002년도 춘계학술대회 논문집
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    • pp.577-583
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    • 2002
  • We have made known the study of shape development of interference device for vehicle noise control. It's primary object greatly attenuate the noise due to transport vehicle by small products installed on the noise barrier edge. Also, it is able to improve the insertion loss of a noise barrier without increasing the height of noise barrier. The present time, we set up a newly manufactured products on the noise barrier edge and testify to it's the performance use of an experiment and evaluation for the reduction of railway noise. In this paper the frequency characteristic of interference device of noise barriers with attached newly developed products in terms of shape, absorptive material and split panel, are examined using field test around of railroad.

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Anti-interference Methods using Vector-based GPS Receiver Mode

  • Viet, Hoan Nguyen;Lee, Suk-Hwan;Kwon, Ki-Ryong
    • 한국멀티미디어학회논문지
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    • 제21권5호
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    • pp.545-557
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    • 2018
  • The Global Positioning System (GPS) has become popular and widely used in many fields from military to civilian applications. However, GPS signals are suffered from interference due to its weak signal over wireless channel. There are many types of interference, such as jamming, blocking multipath, and spoofing, which can mislead the operation of GPS receiver. In this paper, vector-based tracking loop model with integrity check is proposed to detect and mitigate the harmful effect of interference on GPS receiver operation. The suggested methods are implemented in the tracking loop of GPS receiver. As a first method, integrity check with carrier-to-noise ratio (C/No) monitoring technique is applied to detect the presence of interference and prevent contaminated channels out of tracking channels to calculate position. As a second method, a vector-based tracking loop using Extended Kalman Filter with adaptive noise covariance according to C/No monitoring results. The proposed methods have been implemented on simulated dataset. The results demonstrates that the suggested methods significantly mitigate interference of Additive White Gaussian Noise (AWGN) and improve position calculation by 44%.

Joint Detection Method for Non-orthogonal Multiple Access System Based on Linear Precoding and Serial Interference Cancellation

  • Li, Jianpo;Wang, Qiwei
    • Journal of Information Processing Systems
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    • 제17권5호
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    • pp.933-946
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    • 2021
  • In the non-orthogonal multiple access (NOMA) system, multiple user signals on the single carrier are superimposed in a non-orthogonal manner, which results in the interference between non-orthogonal users and noise interference in the channel. To solve this problem, an improved algorithm combining regularized zero-forcing (RZF) precoding with minimum mean square error-serial interference cancellation (MMSE-SIC) detection is proposed. The algorithm uses RZF precoding combined with successive over-relaxation (SOR) method at the base station to preprocess the source signal, which can balance the effects of non-orthogonal inter-user interference and noise interference, and generate a precoded signal suitable for transmission in the channel. At the receiver, the MMSE-SIC detection algorithm is used to further eliminate the interference in the signal for the received superimposed signal, and reduce the calculation complexity through the QR decomposition of the matrix. The simulation results show that the proposed joint detection algorithm has good applicability to eliminate the interference of non-orthogonal users, and it has low complexity and fast convergence speed. Compared with other traditional method, the improved method has lower error rate under different signal-to-interference and noise ratio (SINR).

변형된 역확산기 기반의 GPS 적응 간섭제거기의 출력 SINR 해석 (Output SINR Analysis of GPS Adaptive Interference Canceler Based on Modified Despreader)

  • 황석승
    • 한국전자통신학회논문지
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    • 제9권2호
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    • pp.195-202
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    • 2014
  • 다양한 상업적, 군사적 방면에서 사용되고 있는 위성항법시스템(Global Positioning System: GPS)은 특정 사용자나 물체의 위치를 추정하기 위해 설계되었다. 정확한 위치추정을 위해 위성항법시스템은 최소 네 개의 위성으로부터 신호를 수신하여야 한다. GPS 수신기는 매우 낮은 신호-대-잡음 비(signal-to-noise ratio: SNR)에서 동작하며, GPS 신호에 비해 매우 높은 전력을 가지는 간섭신호들에 의해 위치추정 성능에 영향을 받을 수 있다. 본 논문에서는 고 전력 간섭들을 정확한 GPS 신호의 도래각(angle-of-arrival: AOA) 정보 없이 제거하는 변형된 역확산기(modified despreader) 기반의 다수개의 GPS 신호를 위한 적응 간섭제거기를 소개한다. 또한 변형된 역환산 빔형성기의 출력에 대한 신호-대-간섭 및 잡음 비(signal-to-interference and noise ratio: SINR)의 수학적 해석을 제공한다. 컴퓨터 시뮬레이션을 통해 고려된 GPS 수신기의 간섭제거성능과 SINR에 대한 수학적 해석을 확인한다.

교통소음제어를 위한 간섭형 방음장치 형상개발에 관한 연구 (A study on the shape development of interference device for vehicle noise control)

  • 장강석;심상덕;김영찬;김두훈
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2000년도 춘계학술대회논문집
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    • pp.1778-1783
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    • 2000
  • When visual intrusion is an important factor, it is desirable to find alternative methods of improving the insertion loss of a noise barrier without increasing the height. Therefore, the primary object of the work attenuates the noise due to transport vehicle by small interference device installed at noise barrier edge. In this paper the performance of noise barriers with attached interference device, in terms of shape, absorptive material and split panel, are examined using the boundary element approach. Also, the scale models are moanted in an anechoic chamber and the frequency of the sound sources are appropriately scaled to simulate full scale site conditions. Lastly, experimental measurements of the designs are executed for a range of frequencies and receiver positions, and are compared with the results of numerical modeling.

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한전 765 kV 2회선 송전선로의 전기환경장애 특성 (Environmental Impact on the KEPCO 765-kV Double Circuit Transmission Line)

  • 이동일;신구용;김정부
    • 대한전기학회논문지:전기물성ㆍ응용부문C
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    • 제48권2호
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    • pp.117-126
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    • 1999
  • The environmental impact of the KEPCO 765-kV transmission line was studied using a full scale test line in order to develop the design technology. Therefore this paper describes an environmental design summary of the audible noise, hum noise, wind noise, radio interference, TV interference and electric field measurement from the KEPRI 765-kV double circuit transmission test line with a bundle of $6-480mm^2$ conductors per phase. The analysis of the test results shows that 6-Rail and 6-Cardinal conductors bundle satisfy the audible noise criterion & TV interference under the stable rainy weather condition and the radio interference level under the fair weather. And the other items are also agreed with the design level criterion for KEPCO 765-kV transmission line.

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RFI에 기인한 안테나 성능 저하 분석 (Analysis of Performance Degradation of Antenna due to Radio Frequency Interference)

  • 이호상;김광호;윤진성;이대희;황찬석;나완수
    • 전기학회논문지
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    • 제66권4호
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    • pp.651-658
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    • 2017
  • This paper proposes an analysis method of performance degradation of antenna due to radio frequency interference between an antenna and adjacent noise sources using active scattering parameters. The radio frequency interference can be analyzed by the measured or simulated scattering parameters and by excited noise sources in the circuit as well. In this paper, a planar inverted-F antenna and a noise source are designed and fabricated to analyze radio frequency interference between the planar inverted-F antenna and noise source. The proposed analysis method uses active scattering parameters, of which verification is experimentally verified, and in simulation as well.

스마트 그리드 시스템을 위한 전력선 통신 시스템의 종단 간 방식의 간섭 제거 기법 (Interference Cancellation Scheme of End-to-End Method in Power Line Communication System for Smart Grid)

  • 서성일
    • 한국인터넷방송통신학회논문지
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    • 제19권2호
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    • pp.41-45
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    • 2019
  • 본 논문은 스마트 그리드를 위한 전력선 통신 시스템에서 데이터 신뢰성을 향상시키는 딥러닝 기반의 종단 간 방식의 간섭 제거 알고리즘에 대해 연구하였다. 본 논문에서 제안한 기법은 딥러닝 기술을 적용하여 채널에서 발생하는 잡음을 예측하여 제거하는 기술로서 수신단에서 딥러닝에 의해 학습된 잡음들을 활용하여 효과적으로 잡음을 제거함으로써 신호의 품질을 향상시킬 수 있다. 딥러닝 기술의 잡음 예측 정확도를 향상시키기 위해 기존의 잡음 형태를 데이터베이스화하여 활용하였다. 채널 모델로서 Middleton Class A 간섭 모델을 사용하였고, 비트 오류율을 평가하여 성능을 검증하였다. 모의실험을 통해 간섭 제거 기법이 적용된 시스템 모델과 이론적인 모델의 비트오류율을 비교하여 제안하는 시스템이 잡음을 효과적으로 제거하여 신호의 품질 성능을 향상시킬 수 있음을 확인하였다. 제안한 시스템 모델은 전력선 통신뿐만 아니라 일반적인 통신 시스템에서도 신호의 품질을 향상시킬 수 있도록 다양하게 적용이 가능하다.