• 제목/요약/키워드: bit error rate

검색결과 1,207건 처리시간 0.045초

A Weighted Block-by-Block Decoding Algorithm for CPM-QC-LDPC Code Using Neural Network

  • Xu, Zuohong;Zhu, Jiang;Zhang, Zixuan;Cheng, Qian
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제12권8호
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    • pp.3749-3768
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    • 2018
  • As one of the most potential types of low-density parity-check (LDPC) codes, CPM-QC-LDPC code has considerable advantages but there still exist some limitations in practical application, for example, the existing decoding algorithm has a low convergence rate and a high decoding complexity. According to the structural property of this code, we propose a new method based on a CPM-RID decoding algorithm that decodes block-by-block with weights, which are obtained by neural network training. From the simulation results, we can conclude that our proposed method not only improves the bit error rate and frame error rate performance but also increases the convergence rate, when compared with the original CPM-RID decoding algorithm and scaled MSA algorithm.

개선된 선 스펙트럼 특성을 갖는 비이진 PPM 기반 초광대역 무선전송 시스템 (Ultra-Wide Bandwidth Systems Using a Non-Binary Pulse Position Modulation with Preferable Line Spectrum Properties)

  • 홍윤표;송홍엽
    • 한국통신학회논문지
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    • 제31권6C호
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    • pp.569-574
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    • 2006
  • PPM(Pulse Position Modulation)을 기반으로 하는 초광대역(ultra-wide bandwidth) 무선전송 시스템의 일반적인 전력 밀도 함수(power spectral density function)를 유도한다. 또한 개선된 선 스펙트럼(line spectrum) 특성과 우수한 BER(Bit Error Rate) 성능을 갖는 초광대역 무선전송 시스템을 제안한다.

디지털 홀로그래픽 데이터 저장 시스템을 위한 1차원 및 2차원 최소 평균-제곱-에러 등화에 관한 연구 (A study on 1 & 2 dimensional minimum mean-squared-error equalization for digital holographic data storage system)

  • 최안식;전영식;정종래;백운식
    • 한국광학회지
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    • 제13권6호
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    • pp.486-492
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    • 2002
  • 본 논문에서는 디지털 홀로그래픽 데이터 저장 시스템에서 2차원 데이터의 저장과 복원 동안에 발생되는 상호 픽셀에 의한 간섭(intersymbol interference:ISI)을 완화하고 bit-error-rate(BER) 성능개선을 위해 1차원 및 2차원 최소 평균-제곱-에러 (minimum mean-squared-error:MMSE) 등화(equalization)를 적용하였다. 홀로그래픽 저장 시스템으로부터 복원된 10개의 페이지에 대해서 등화 수행전보다 1차원 및 2차원 MMSE등화 적용 후, BER과 signal-to-noise ratio(SNR)이 향상됨을 보였다.

Performance Analysis of a Two-Hop Fixed-Gain MIMO Multiuser Relay Network with End-to-End Antenna Selection

  • Li, Guangping;Blostein, Steven David;Zhang, Guangchi;Feng, Jiuchao
    • ETRI Journal
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    • 제34권2호
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    • pp.264-267
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    • 2012
  • This letter analyzes the performance of a two-hop MIMO multiuser relay network with a fixed gain amplify-and-forward protocol and antenna selection at the transmitter and receiver. A new expression for the cumulative distribution function of the highest instantaneous end-to-end signal-to-noise ratio is derived. Based on the above result, closed-form expressions for outage probability and bit error rate are presented. Also, the diversity order of the system is determined. Finally, computer simulations are compared to the analytical results, and insights and observations are provided.

다중경로 페이딩 채널에서 DAC 양자화 오차에 대한 IEEE P802.15.3a 멀티밴드 UWB 송수신기 성능 분석 (Performance Analysis of IEEE P802.15.3a Multi-band UWB Transceiver for DAC Quantization Error in Fading Channel)

  • 정성원;이승윤;임승호;박규호
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2003년도 통신소사이어티 추계학술대회논문집
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    • pp.216-219
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    • 2003
  • In this paper, we present performance analysis of an IEEE P802.15.3a high rate wireless personal area network transceiver. This physical layer standard uses QOSK as its sub-channel modulation scheme and orthogonal frequency domain modulation (OFDM) for sub-bands. OFDM is used for each sub-band so that multi-path effects are absorbed by equalizer and guard, and fading can be approximately modeled as additive white Gaussian noise. In multi-band ultra-wideband system, DAC quantization error is important noise source since high resolution conversion cannot be used due to high power consumption. Simulation result shows that, to get 640-Mbps throughput, at least 5-bits precision is necessary to maintain bit-error rate under 10$\^$-2/, which can be lowered, with channel coding, to 10$\^$-6/ that is the bit-error rate required by IEEE 802.15 upper protocol layer, in 4-meter LOS fading channel.

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갈릴리안 광학계를 사용한 IM/DD 광무선통신 시스템에서 830[nm] 광파장에 대한 전송거리 제한 해석 (Numerical Study on the Link Range of the IM/DD Wireless Optical Communication at 830[nm] Optical Wavelength using Galilean Optics)

  • 홍권의;고성원;조정환
    • 조명전기설비학회논문지
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    • 제25권11호
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    • pp.123-129
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    • 2011
  • In terrestrial wireless optical communication links, atmospheric effects including turbulence, absorption and scattering have significant impact on the system performance. Based on the analysis of transmission in atmospheric channel concerning 830[nm] wavelength diode laser beam, performance of free space optical (FSO) link utilizing Galilean optics as a laser beam transmitting and receving optics, PIN photodiode as a detecting device. In this paper we designed optical link equation for received optical power and we analyze the atmospheric effects on the signal to noise ratio (SNR) and bit error rate (BER) of an terrestrial FSO system. We show that the possible communication distance for BER=$10^{-9}$ in proposed adverse atmospheric conditions.

On the Performance of the Block-Based Selective OFDM Decode-and-Forward Relaying Scheme for 4G Mobile Communication Systems

  • Yang, Wendong;Cai, Yueming
    • Journal of Communications and Networks
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    • 제13권1호
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    • pp.56-62
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    • 2011
  • In this paper, we propose a block-based selective orthogonal frequency division multiplexing (OFDM) decode-and-forward relaying scheme for 4G mobile communication systems. In the scheme, an OFDM symbol is divided into blocks and one relay is selected for each block. Theoretical outage performance and error performance are analyzed and evaluated. A unified outage expression is given for our scheme and the other two schemes and the lower bound of the bit error rate of the three schemes is also obtained. The effect of the coherence bandwidth on the proposed scheme is also investigated. Monte Carlo simulations are carried out to validate our analysis. The scheme can obtain a good tradeoff between complexity and performance and can be used in future 4G mobile communication systems.

레일리페이딩 환경에서 복호 후 재전송방식을 위한 부분적 릴레이 선택방식 연구 (Partial Relay Selection for Decode and Forward over Rayleigh Fading Channels)

  • 보 뉘엔 �o 바오;공형윤
    • 한국통신학회논문지
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    • 제34권7A호
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    • pp.523-529
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    • 2009
  • This paper provides closed form expressions for the evaluation of the end-to-end outage probability, symbol error rate, bit error rate and average capacity of the partial-based Decode-and-Forward (DF) relay selection scheme with an arbitrary number of relays. In a comparison with the performance of systems that exploit Amplify-and-Forward (AF), it can be seen that the performance of our proposed protocol converges to that of partial-based AF relay selection in high SNR regime. We also perform Monte-Carlo simulations to validate the analysis.

와이브로 단말의 자동 이득 제어 (Automatic Gain Control in WiBro AT (Access Terminal))

  • 이용수;김영일;김환우
    • 한국통신학회논문지
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    • 제35권1A호
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    • pp.10-15
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    • 2010
  • 본 논문에서는 WiBro (Wireless Broadband) 단말 시스템에서의 실용적인 자동 이득 제어 방법을 제안한다. 이 시스템의 하향링크 패킷은 프리앰블 (Preamble) 심볼과 데이터 (data) 심볼로 구성되어 있으며, 프리앰블 심볼은 자동 이득 제어, 자동 주파수 제어 그리고 하향링크의 채널을 측정하는 용도로 쓰이며, 데이터 심볼은 트래픽을 전달하는 수단으로 주로 쓰인다. 본 논문에서는 이론적인 비트오율 (Bit Error Rate)과 모의실험을 통한 결과와 비교를 해서 이 시스템의 자동 이득 제어를 위한 최적의 매개변수를 찾고, 초기 동기 전의 자동 이득 제어 방법에 관한 효과적인 알고리듬을 제안한다.

공간적 빔 세기 불 균일성을 가지는 디지털 홀로그래픽 데이터 저장 시스템을 위한 수정된 패리티 코딩 (Modified parity coding for digital holographic data storage system with spatial beam intensity variations)

  • 최안식;전영식;백운식
    • 한국광학회지
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    • 제14권2호
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    • pp.150-154
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    • 2003
  • 본 논문에서는 홀로그래픽 데이터 저장시스템에서 발생되는 공간적 빔 세기의 불 균일성 때문에 발생되는 에러를 줄이기 위한 수정된 패리티 코딩기법들을 소개한다. 일반적인 패리티 코딩과 수정된 패리티 코딩 기법들에 대한 인코딩과 디코딩 방법에 대해 설명하였으며, 실험결과로부터 패리티 코딩과 수정된 패리티 코딩기법들의 bit-error-rate(BER)성능을 비교하였다.