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JOINT ITERATIVE DECODING FOR SIMPLE-ENCODING SYSTEMATIC IRREGULAR-LDPC-BASED CODED COOPERATION IN NON-IDEAL RELAY CHANNEL

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Journal of Electronics(China) 2010年第3期27卷 305-315页

作者： Chen Jingwen yang fengfan Luo Lin Tho Le-Ngoc College of Information Science and Technology Nanjing University of Aeronautics and Astronautics Nanjing 210016 China College of Information Science and Engineering Southeast University Nanjing 210096 China Department of Electrical and Computer Engineering McGill University Montreal H3A2A7 Quebec Canada

In this paper, a new kind of simple-encoding irregular systematic LDPC codes suitable for one-relay coded cooperation is designed, where the proposed joint iterative decoding is effectively performed in the destination which is in accordance with the corresponding joint Tanner graph characterizing two different component LDPC codes used by the source and relay in ideal and non-ideal relay cooperations. The theoretical analysis and simulations show that the coded cooperation scheme obviously outperforms the coded non-cooperation one under the same code rate and decoding complex. The significant performance improvement can be virtually credited to the additional mutual exchange of the extrinsic information resulted by the LDPC code employed by the source and its counterpart used by the relay in both ideal and non-ideal cooperations.

关键词： Cooperative communication Low-density parity-check code Relay channel Joint Tanner graph Joint iterative decoding

HIGH-PERFORMANCE SIMPLE-ENCODING GENERATOR-BASED SYSTEMATIC IRREGULAR LDPC CODES AND RESULTED PRODUCT CODES

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Journal of Electronics(China) 2007年第5期24卷 613-621页

作者： yang fengfan Ye Ming Luo Lin Dept of Electronic Engineering Nanjing University of Aeronautics ＆ Astronautics Nanjing 210016 China Dept of Radio Engineering Southeast University Nanjing 210096 China

Low-Density Parity-Check (LDPC) code is one of the most exciting topics among the coding theory *** is of great importance in both theory and practical communications over noisy *** most advantage of LDPC codes is their relatively lower decoding complexity compared with turbo codes,while the disadvantage is its higher encoding *** this paper,a new ap- proach is first proposed to construct high performance irregular systematic LDPC codes based on sparse generator matrix,which can significantly reduce the encoding complexity under the same de- coding complexity as that of regular or irregular LDPC codes defined by traditional sparse parity-check ***,the proposed generator-based systematic irregular LDPC codes are adopted as con- stituent block codes in rows and columns to design a new kind of product codes family,which also can be interpreted as irregular LDPC codes characterized by graph and thus decoded ***, the performance of the generator-based LDPC codes and the resultant product codes is investigated over an Additive White Gaussian Noise (AWGN) and also compared with the conventional LDPC codes under the same conditions of decoding complexity and channel noise.

关键词： LDPC code Iterative decoding Parity-check Generator matrix Product code Graph Kronecker product

The novel transmission scheme with CAT Ethernet cable and SFP for White Rabbit

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Radiation Detection Technology and Methods 2021年第2期5卷 290-296页

作者： Yanke Cai Jie Zhang Yunhua Sun fengfan yang Xiaoshan Jiang Changge Zi Cong He Shanshan Cui State Key Laboratory of Particle Detection and Electronics Institute of High Energy PhysicsChinese Academy of Sciences(CAS)Beijing 100049China University of Chinese Academy of Sciences(UCAS) Beijing 100049China

Background White Rabbit(WR)is a deterministic Ethernet-based network for general-purpose data transfer and subnanosecond time synchronization in large distributed *** has been used in Large Hadron Collider and Large High-Altitude Air Shower Observatory for physics *** WR mainly uses the optical fiber for data transmission between WR *** off-the-shelf Direct Attach Cable is not suitable for WR network at 100m level *** the lower cost of Category(CAT)Ethernet cable compared to optical fiber and the demand of remote power supply in distributed system at 100m level length,we developed a novel transmission scheme with CAT Ethernet cable for *** The novel transmission scheme uses the CAT Ethernet cable and small form-factor pluggable connector which is compatible with the optical *** scheme only uses two pairs of twisted lines in the CAT Ethernet cable for data uplink and *** other two pairs of twisted lines are used for remote power *** and conclusion The novel transmission scheme could use the CAT Ethernet cable to complete remote power supply and time synchronization with expected time offset of less than 100 ps and standard deviation of less than 20 ps in the WR distributed *** distance of distributed nodes could be 80m with one CAT 7 Ethernet cable or 150m with relay transceiver connecting two CAT 7 Ethernet *** the short-distance scenarios,the novel transmission scheme has lower cost than the optical fiber and additional power supply function.

关键词： White Rabbit Time synchronization SFP CAT Ethernet cable Remote power supply

Effect of annealing treatment on the structural, optical, and electrical properties of Al-doped ZnO thin films

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Rare Metals 2007年第3期26卷 247-253页

作者： LI Li FANG Liang CHEN Ximing LIU Gaobin LIU Jun yang fengfan FU Guangzong KONG Chunyang College of Photoelectric Engineering Chongqing University of Posts and Telecommunications Chongqing 400065 China Department of Applied Physics Chongqing University Chongqing 400044 China Department of Physics Chongqing Normal University Chongqing 400047 China

Highly conductive and transparent Al-doped ZnO （AZO） thin films were prepared from a zinc target containing Al （1.5 wt.%） by direct current （DC） and radio frequency （RF） reactive magnetron sputtering. The structural, optical, and electrical properties of AZO films as-deposited and submitted to annealing treatment （at 300 and 400℃, respectively） were characterized using various techniques. The experimental results show that the properties of AZO thin films can be further improved by annealing treatment. The crystallinity of ZnO films improves after annealing treatment. The transmittances of the AZO thin films prepared by DC and RF reactive magnetron sputtering are up to 80% and 85% in the visible region, respectively. The electrical resistivity of AZO thin films prepared by DC reactive magnetron sputtering can be as low as 8.06 x 10-4 Ωcm after annealing treatment. It was also found that AZO thin films prepared by RF reactive magnetron sputtering have better structural and optical properties than that prepared by DC reactive magnetron sputtering.

关键词： AZO thin films structure optical and electrical properties annealing transmittance spectra electrical resistivity

PERFORMANCE OF SIMPLE-ENCODING IRREGULAR LDPC CODES BASED ON SPARSE GENERATOR MATRIX

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Transactions of Nanjing University of Aeronautics and Astronautics 2006年第3期23卷 202-207页

作者：唐蕾仰枫帆南京航空航天大学信息科学与技术学院

A new method for the construction of the high performance systematic irregular low-density paritycheck （LDPC） codes based on the sparse generator matrix （G-LDPC） is introduced. The code can greatly reduce the encoding complexity while maintaining the same decoding complexity as traditional regular LDPC （H-LDPC） codes defined by the sparse parity check matrix. Simulation results show that the performance of the proposed irregular LDPC codes can offer significant gains over traditional LDPC codes in low SNRs with a few decoding iterations over an additive white Gaussian noise （AWGN） channel.

关键词： belief propagation iterative decoding algorithm sparse parity-check matrix sparse generator matrix H LDPC codes G-LDPC codes

V-BLAST BASED LDPC-CODED RELAY COOPERATION

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Transactions of Nanjing University of Aeronautics and Astronautics 2013年第4期30卷 374-382页

作者：唐蕾仰枫帆张顺外范立行 College of Electronics and Information Engineering Nanjing University of Aeronautics and Astronautics

An efficient LDPC-coded multi-relay cooperation architecture is proposed based on virtual vertical Bell Labs layered space-time （V-BLAST） processing for uplink communication, where minimum-mean-square-error （MMSE） and BP-based joint iterative decoding based on the introduced muhi-layer Tanner graph are effectively de- signed to detect and decode the corrupted received sequence at the destination. By introducing V-BLAST transmis- sion to the coded multi-relay cooperation, relays send their streams of symbols simultaneously, which increases the data rate and significantly reduces the transmission delay. The theoretical analysis and numerical results show that the new LDPC coded cooperation scheme outperforms the coded non-cooperation under the same code rate, and it also achieves a good trade-off among the performance, signal delay, and the encoding complexity associated with the number of relays. The performance gain can be credited to the proposed V-BLAST processing architecture and BP-based joint iterative decoding by the introduced multi-layer Tanner graph at a receiver-side.

关键词： coded multi-relay cooperation vertical Bell Labs layered space-time processing (V-BLAST) mini-mum-mean-square-error detector~ joint decoding multi-layer Tanner graph

基于非规则LDPC码的协作MIMO系统性能分析

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数据采集与处理 2013年第6期28卷 714-718页

作者：张艳仰枫帆南京航空航天大学电子信息工程学院南京210016 南京信息职业技术学院电子信息学院南京210032

提出了一种基于非规则低密度奇偶校验码(Low density parity check codes,LDPC)码设计的用户协作分集方案,并且给出了准静态的瑞利衰落信道下单用户单中继环境下的3种中继协议的性能比较和中断概率理论推导,比较分析了采用编码协作策略... 详细信息

提出了一种基于非规则低密度奇偶校验码(Low density parity check codes,LDPC)码设计的用户协作分集方案,并且给出了准静态的瑞利衰落信道下单用户单中继环境下的3种中继协议的性能比较和中断概率理论推导,比较分析了采用编码协作策略的双用户多中继环境下的系统的误比特性能和中断概率的仿真图。结果表明采用了非规则LDPC码的编码协作协议的系统性能明显优于放大转发(Amplify forward,AF)协议和解码转发(Decode forward,DF)协议,误码率分别提高了0.4dB和0.8dB,中断概率性能也明显提高,性能得到显著改善。

关键词：编码协作协作MIMO 误比特率中断概率非规则LDPC

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新型卫星导航系统在半盲信道中的抗干扰分析

数据采集与处理 2012年第5期27卷 595-601页

作者：丁颖婷仰枫帆南京航空航天大学电子信息工程学院南京210016

新型卫星导航系统是中国自行研制的卫星导航系统,其主要特点是在多输入多输出系统(Multiple input multiple output,MIMO)中进行抗干扰处理。本文提出了新型卫星导航系统在半盲MIMO信道中的抗干扰算法,利用MATLAB进行仿真,比较了确定信... 详细信息

新型卫星导航系统是中国自行研制的卫星导航系统,其主要特点是在多输入多输出系统(Multiple input multiple output,MIMO)中进行抗干扰处理。本文提出了新型卫星导航系统在半盲MIMO信道中的抗干扰算法,利用MATLAB进行仿真,比较了确定信道和半盲信道在改变干扰位置、改变接收天线数目以及改变阵列类型情况下的抗干扰性能。仿真结果表明了半盲信道抗干扰算法的实用性和优越性。

关键词：卫星导航系统 MIMO 抗干扰半盲信道

LDPC结合垂直分层空时码的迭代检测算法的研究

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南京邮电大学学报（自然科学版） 2015年第3期35卷 47-51页

作者：张艳仰枫帆南京信息职业技术学院电子信息学院江苏南京210032 南京航空航天大学电子信息工程学院江苏南京210016

文中提出了基于球形检测的Fincke-Pohst-MAP(FP-MAP)的联合迭代检测算法,介绍了LDPC码结合垂直分层空时码(V-BLAST)在协作MIMO系统中的应用。理论分析和推导了联合迭代的具体过程,通过仿真结果的研究表明,FP-MAP球形检测算法与迫零排序... 详细信息

文中提出了基于球形检测的Fincke-Pohst-MAP(FP-MAP)的联合迭代检测算法,介绍了LDPC码结合垂直分层空时码(V-BLAST)在协作MIMO系统中的应用。理论分析和推导了联合迭代的具体过程,通过仿真结果的研究表明,FP-MAP球形检测算法与迫零排序加干扰抵消(ZF-OSIC)算法和基于递推最小二乘法的判决反馈均衡(RLS-DFE)算法相比,误码率的性能分别提高了1 dB和0.3 dB左右,而且FP-MAP算法的性能最接近于ML检测。最后还将LDPC码、卷积码和Turbo码与V-BLAST级联的协作MIMO系统进行了比较分析,仿真结果可知LDPC级联系统在较高信噪比区域时的性能更优越。

关键词： LDPC码 V-BLAST 协作MIMO 球形算法迭代检测