• Title/Summary/Keyword: Signal Interference

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Interference Signal Control using Neural Network in Digital Mobile Communication (이동 무선 통신에서 신경망을 이용한 간섭 신호 제어)

  • 나상동;배철수
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.2 no.1
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    • pp.109-116
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    • 1998
  • In this paper, a back propagation neural network teaming algorithm based on the complex multilyer perceptron is represented for suppressing narrowband interference of the received signals in DS-SS mobile communication system. We proposed neural network adaptive correlator(NNAC) which has fast convergence rate and good performance with combining back propagation neural network and the receiver of DS-SS. We analyzed and proved that NNAC has lower bit error probability than that of traditional RAKE receiver through results of computer simulation in the presence of the tone and narrow-band interference and the co-channel interference.

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Interference Reduction Scheme for Mobile WiMAX in an Indoor environment (실내 환경의 Mobile WiMAX 시스템을 위한 간섭 완화 기술에 대한 연구)

  • Oh, Yong-Il;Ha, Kwang-Jun;Koo, Sung-Wan;Kim, Jin-Young
    • 한국정보통신설비학회:학술대회논문집
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    • 2008.08a
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    • pp.454-458
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    • 2008
  • This article describes an interference reduction scheme for Mobile WiMAX in an indoor environment. The feasibility of user deployed femtocells in the same frequency channel as an existing macro cell network is investigated. One of the important requirements for co-channel operation of femtocells such as auto-configuration and self optimization are discussed. In femtocell deployments, leakage of the pilot signal to the outside of a house can result of the higher number of mobility events caused by passing user of macrocell. This interference effect can be minimized by reducing the pilot power using proper scheme. This paper introduces existing auto-configuration method of power control and proposed interference reduction scheme using power control for Mobile WiMAX in an indoor environment.

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Performance Evaluation of Short-Range Communication Home Network in the Presence of Co-Channel Interference (동일채널간섭이 존재하는 홈 네트워크에서 근거리 통신 시스템의 성능 평가)

  • Roh Jae-Sung
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2006.05a
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    • pp.555-558
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    • 2006
  • Bluetooth is an open specification technology for short-range wireless connectivity between electronic devices. This paper analyzes the effects of interference on the performance of a Bluetooth system. Two performance criteria used in the study are the signal to interference power ratio (SIR) and the bit error rate (BER) of the bits received. The interference from various sources on the performance of a Bluetooth device is analyzed, and these quantities are plotted against Eb/No and SIR for various channel conditions in figures.

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Direct-band spread system for neural network with interference signal control (직접 대역 확산 시스템에서 신경망을 이용한 간섭 신호 제어)

  • Cho, Hyun-Seob
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.14 no.3
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    • pp.1372-1377
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    • 2013
  • In this Paper, a back propagation neural network learning algorithm based on the complex multilayer perceptron is represented for controling and detecting interference of the received signals in cellular mobile communication system. We proposed neural network adaptive correlator which has fast convergence rate and good performance with combining back propagation neural network and the receiver of cellular. We analyzed and proved that NNAC has lower bit error probability than that of traditional RAKE receiver through results of computer simulation in the presence of the tone and narrow-band interference and the co-channel interference.

A NNAC using narrowband interference signal control in cellular mobile communication systems (셀룰라 이동 통신에서 NNAC를 이용한 협대역 간섭 신호 제어)

  • Cho, Hyun-Seob
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.10 no.3
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    • pp.542-546
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    • 2009
  • In this Paper, a back propagation neural network learning algorithm based on the complex multilayer perceptron is represented for controling and detecting interference of the received signals in cellular mobile communication system. We proposed neural network adaptive correlator which has fast convergence rate and good performance with combining back propagation neural network and the receiver of cellular. We analyzed and proved that NNAC has lower bit error probability than that of traditional RAKE receiver through results of computer simulation in the presence of the tone and narrow - band interference and the co-channel interference.

A Study on Interference Cancelling Receiver with Adaptive Blind CMA Array (적응 블라인드 CMA 어레이를 이용한 간섭 제거 수신기에 관한 연구)

  • 우대호;변윤식
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.27 no.4A
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    • pp.330-335
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    • 2002
  • In the direct sequence code division multiple access system, the problem of multiple access interference due to multiple access is generated. A interference cancelling receiver is used to solve this problem. The conventional interference cancelling receiver is structure of successive interference canceller using antenna array. In this structure, the difference of between method I and method II depends on updating weight vector. In this paper, the adaptive blind CMA array interference cancelling receiver using cost function of constant modulus algorithms is proposed to update weight vector at conventional structure. The simulation compared the proposed interference cancelling receiver with two conventional interference cancelling receivers by signal to interference ratio and bit error rate curve under additive white Gaussian noise environment. The simulation results show that the proposed receiver has about the gain of SIR of 1.5[dB] more than method I which is conventional receiver at SIR curve, and about the gain of SIR of 0.5(dB) more than method II. In BER curve, the proposed IC receiver about the gain of SNR of 2[dB] more than method I and about the gain of SNR of 0.5[dB] more than method If, Thus, the proposed interference cancelling receiver has the higher performance than conventional interference cancelling receivers.

A BUSSGANG-TYPE ALGORITHM FOR BLIND SIGNAL SEPARATION

  • Choi, Seung-Jin;Lyu, Young-Ki
    • Proceedings of the IEEK Conference
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    • 1998.10a
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    • pp.1191-1194
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    • 1998
  • This paper presents a new computationally efficient adaptive algorithm for blind signal separation, which is able to recover the narrowband source signals in the presence of cochannel interference without a prior knowledge of array manifold. We derive a new blind signal separation algorithm using the Natural gradient 〔1〕from an information-theoretic approach. The resulting algorithm has the Bussgang property which has been widely used in blind equalization 〔12〕. Extensive computer simulation results comfirm the validity and high performance of the proposed algorithm.

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Adaptive array processing (적응 어레이 프로세싱)

  • 이상철
    • 전기의세계
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    • v.29 no.9
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    • pp.584-593
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    • 1980
  • Conventional radar antenna systems are susceptible to performance degradation caused by unwanted signals received via the antenna sidelobes and/or mainlobes. Adaptive array systems offer possible solution to this interference problem by automatically steering nulls to unwanted signals providing significant system performance improvement. Another important andvantage of the adaptive array is its self-optimization capability which uses the collective incoming noise data for the nulling purposes. This paper provides a tutorial introduction to adaptive arrays as well as some new development of recent research in this area. Optimum link between the antenna theory and signal processing has been sought by illustrating the gain patterns and output signal-to-noise ratio. Signal acqusition methods are shown including a new attempt of the use of spread-spectrum techniques in conjuction with array systems.

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Filtering Techniques for Chaotic Signals

  • Lee, Chung-Yong
    • The Journal of the Acoustical Society of Korea
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    • v.15 no.3E
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    • pp.45-59
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    • 1996
  • Generalized iterative methods for reducing noise in contaminated chaotic signals are proposed. These methods minimize a cost function composed of two parts : one containing information that represents how close enhanced signals are to the observed signal and another composed of constraints that fit the dynamics of the system. The convergence conditions and the error systems of the proposed are investigated. As one aspect of noise reduction, the suppression or cancellation of a chaotic interference signal is discussed.

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An Effective Mitigation Method on the Signal-Integrity Effects by Splitting of a Return Current Plane (귀환 전류 평면의 분할에 기인하는 신호 무결성의 효과적인 대책 방법)

  • Jung, Ki-Bum;Jun, Chang-Han;Chung, Yeon-Choon
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.19 no.3
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    • pp.366-375
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    • 2008
  • Generally a return current plane(RCP) of high speed digital and analog part is partitioned. This is achieved in order to decrease the noise interference between subsystem in PCBs(Printed Circuit Boards). However, when the connected signal line exists between each sub system, this partition will cause unwanted effects. In a circuital point of view, RCP partition has a bad influence upon signal integrity. In a EMI(Electromagnetic Interference) point of view, the partition of the return current plane becomes a primary factor to increase the radiated emission. Component bridge(CB) is usecl for the way of maintaining signal integrity, still specific user's guide doesn't give sufficient principle. In a view point of signal integrity, design principle of multi-CB using method will be analyzed by measurement and simulation. And design principle of noise mitigation will be provided. Generally interval of CB is ${\lambda}/20$ ferrite bead. In this study. When multi-CB connection is applied, design principle of ferrite bead and chip resistor is proved by measurement and simulation. Multi-connected chip resistance$(0{\Omega})$ is proved to be more effective design method in the point of signal integrity.