• Title/Summary/Keyword: bit error rate

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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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    • v.12 no.8
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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.

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

  • Hong Yun-Pyo;Song Hong-Yeop
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.31 no.6C
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    • pp.569-574
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    • 2006
  • We derive the general power spectral density of functions of ultra-wide bandwidth (UWB) systems using a pulse position modulation. We propose a new UWB system with a preferable line spectrum properies and a good bit error rate performance.

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

  • 최안식;전영식;정종래;백운식
    • Korean Journal of Optics and Photonics
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    • v.13 no.6
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    • pp.486-492
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    • 2002
  • In this paper. we presented 1 & 2 dimensional minimum mean-squared-error (MMSE) equalization scheme in a digital holographic data storage system to improve bit-error-rate (BER) and to mitigate inter-symbol interference (ISI) which were generated during the data storage and retrieval processes. We showed experimentally for ten data pages retrieved from the holographic storage system that BER and signal-to-noise ratio (SNR) were improved by adopting MMSE equalization.

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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    • v.34 no.2
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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.

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

  • 정성원;이승윤;임승호;박규호
    • Proceedings of the IEEK Conference
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    • 2003.11c
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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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Numerical Study on the Link Range of the IM/DD Wireless Optical Communication at 830[nm] Optical Wavelength using Galilean Optics (갈릴리안 광학계를 사용한 IM/DD 광무선통신 시스템에서 830[nm] 광파장에 대한 전송거리 제한 해석)

  • Hong, Kwon-Eui;Ko, Sung-Won;Cho, Jung-Whan
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.25 no.11
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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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    • v.13 no.1
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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.

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

  • Bao, Vo Nguyen Quoc;Kong, Hyung-Yun
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.34 no.7A
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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.

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

  • Lee, Yong-Su;Kim, Young-Il;Kim, Whan-Woo
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.35 no.1A
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    • pp.10-15
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    • 2010
  • This paper proposes a practical method for AGC (Automatic Gain Control) in WiBro (Wireless Broadband) AT (Access Terminal) system. Downlink packets in this system consist of preamble symbols for AGC, AFC (Automatic Frequency Control) and other purposes and data symbols for traffic transmission. In this paper we compare theoretical BER (Bit Error Rate) performance with simulation results and produce optimum parameters for AGC in this system. And we propose an efficient AGC scheme before synchronization.

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

  • Choi, An-Sik;Jun, Young-Sik;Baek, Woon-Sik
    • Korean Journal of Optics and Photonics
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    • v.14 no.2
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    • pp.150-154
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    • 2003
  • In this paper, we introduce modified parity coding methods to reduce the errors caused by spatial beam intensity variations in a holographic data storage system. We explained the encoding and decoding process of the conventional parity coding and the modified parity coding techniques. We compared the bit-error-rate (BER) performances of the conventional parity coding and the modified parity coding techniques from experimental evaluation.