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Chinese Journal of Lasers 1998年第2期B7卷 31-36页

作者： WANG Lindou(department of electronic engineering,Tianjin University,Tianjin 300072,china) Tianjin Univ Tianjin China

ＣｏｍｐａｃｔＨｉｇｈ┐ｐｅｒｆｏｒｍａｎｃｅＢｕｌｋＯｐｔｉｃａｌＩｓｏｌａｔｏｒＷＡＮＧＬｉｎｄｏｕ（ＤｅｐａｒｔｍｅｎｔｏｆＥｌｅｃｔｒｏｎｉｃＥｎｇｉｎｅｅｒｉｎｇ，ＴｉａｎｊｉｎＵｎｉｖｅｒｓｉｔｙ，Ｔｉａ... 详细信息

ＣｏｍｐａｃｔＨｉｇｈ┐ｐｅｒｆｏｒｍａｎｃｅＢｕｌｋＯｐｔｉｃａｌＩｓｏｌａｔｏｒＷＡＮＧＬｉｎｄｏｕ（ＤｅｐａｒｔｍｅｎｔｏｆＥｌｅｃｔｒｏｎｉｃＥｎｇｉｎｅｅｒｉｎｇ，ＴｉａｎｊｉｎＵｎｉｖｅｒｓｉｔｙ，Ｔｉａｎｊｉｎ３０００７２，Ｃｈｉｎａ）...

关键词： isolaton fiber optic communication bulk isolator

User-perceived e-mail service QoS parameters and measurement

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The Journal of china Universities of Posts and Telecommunications 2010年第3期17卷 85-90页

作者： LI Yong-zhi , LIU Feng, LEI Zhen-ming, CHEN Ling School of Information and communication engineering, Beijing University of Posts and Telecommunications, Beijing 100876, china School of Information and communication engineering Beijing University of Posts and Telecommunications Beijing 100876 China

A group of quality of service （QoS） parameters of electronic mail （e-mail） traffic are proposed from users＇ perspective. These parameters cover three fields： delay, throughput and usability. Concept and algorithm of each parameter are presented and its effect on user perceptions is described. In order to evaluate the effectiveness of these parameters, an active measurement system is implemented. Measured results show that the group of QoS parameters we proposed can be used to get a comprehensive view of user-perceived e-mail service QoS.

关键词： user perceptions e-mail service QoS active measurement

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Error exponents for two-hop Gaussian multiple source-destination relay channels

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Science china(Information Sciences) 2012年第2期55卷 348-359页

作者： DENG PanLiang1,3,LIU YuanAn1,3,XIE Gang2,3,WANG XiaoYu1,3,TANG BiHua1,3 & SUN JianFeng1,3 1School of electronic engineering,Beijing University of Posts and Telecommunications,Beijing 100876,china 2School of Information and communication engineering,Beijing University of Posts and Telecommunications,Beijing 100876,china 3Key Laboratory of Universal Wireless communication,Ministry of Education,Beijing 100876,china School of electronic engineering Beijing University of Posts and Telecommunications Beijing China Key Laboratory of Universal Wireless communication Ministry of Education Beijing China School of Information and communication engineering Beijing University of Posts and Telecommunications Beijing China

We investigate the two-hop multiple source-destination relay channels using the rate splitting trans-mission scheme where each source can split its message into private and public *** determine the system error probability via integrated exponent function under amplify-and-forward(AF)and decode-and-forward(DF)relay *** most significant difference between AF and DF system error probability evaluations lies in a minimized cut-set bound of transmission rate under the DF *** are many cases among transmission rate intervals for different system parameters(*** power)and it is extremely complex to derive the system error probability for the DF *** obtain a relatively simple result,which unifies various cases by a few *** results show that the system error probability decreases with the increase of the public ***,in order to draw deep insight into the reliability requirement of each source node in this network,we provide the error exponent region(EER)for different source nodes to show the trade-off of error probability among source nodes.

关键词： error exponent error exponent region rate splitting multiple source-destination relay channel

Magnetic and dielectric properties of low temperature fired ferrite/ceramic composite materials

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Progress in Natural Science:Materials International 2011年第1期21卷 21-26页

作者： Wei-wei LING~(1,2),Huai-wu ZHANG~1,Ying HE~1,Yuan-xun LI~1,Yun-yan WANG~1 1.State Key Laboratory of electronic Thin Films and Integrated Devices, University of electronic Science and Technology of china,Chengdu 610054,china 2.department of communication engineering,Chengdu University of Information Technology, Chengdu 610225,china State Key Laboratory of electronic Thin Films and Integrated Devices University of Electronic Science and Technology of China Chengdu 610054 China department of communication engineering Chengdu University of Information Technology Chengdu 610225 China

Ni-Cu-Zn ferrite/CaTiO3and Ni-Cu-Zn ferrite/BaTiO3composites which can be applied in low temperature co-fired ceramic（LTCC） technology were synthesized by conventional solid-state reaction at temperature lower than 950℃.Influence of the microstructures and the gap parameterδ/D on the complex permeability of the above two composites was *** modifiedδ/D values of the above two composites show a good fit to the magnetic circuit *** dielectric properties of the composites were predicted by the Maxwell-Garnctt effective medium theory and the discrepancy between measured and calculated values was analyzed.

关键词： ferrite/ceramic composite low temperature co-fired ceramic(LTCC) solid-state reaction magnetic properties dielectric properties

Robust multiuser MIMO scheduling algorithms with imperfect CSI

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Science china(Information Sciences) 2012年第4期55卷 815-826页

作者： MAO JunLing 1,3,GAO JinChun 1,3,LIU YuanAn 1,3,XIE Gang 2,3 & ZHANG Jian 1,3 1 School of electronic engineering,Beijing University of Posts and Telecommunications,Beijing 100876,china 2 School of Information and communication engineering,Beijing University of Posts and Telecommunications,Beijing 100876,china 3 Key Lab of Universal Wireless communications,Ministry of Education,Beijing University of Posts and Telecommunications,Beijing 100876,china School of electronic engineering Beijing University of Posts and Telecommunications Beijing China Key Lab of Universal Wireless communications Ministry of Education Beijing University of Posts and Telecommunications Beijing China School of Information and communication engineering Beijing University of Posts and Telecommunications Beijing China

Robust multiuser multiple-input-multiple-output (MIMO) scheduling algorithms are proposed in this *** imperfect channel state information (CSI),traditional scheduling algorithms for the multiuser MIMO system based on the zero forcing precoding scheme will lose some performance due to the multi-user interference (MUI).In order to improve the system average throughput,we study the robust multiuser MIMO scheduling problem with imperfect *** the average capacity formula,we derive a robust factor which can transform the robust multiuser MIMO scheduling problem into the traditional one,thus most existing non-robust scheduling algorithms can be robust if this factor is *** results show that compared with the traditional algorithms,the proposed robust algorithms can improve the system average throughput significantly under the CSI error environment.

关键词： multiuser MIMO (MU-MIMO) scheduling robust imperfect CSI

An integrated quantum secure communication system

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Science china(Information Sciences) 2011年第12期54卷 2598-2611页

作者： DAI WenChao, LU Yuan, ZHU Jun & ZENG GuiHua State Key Lab of Advanced Optical communication Systems and Networks, department of electronic engineering Shanghai Jiaotong University, Shanghai 200240, china State Key Lab of Advanced Optical communication Systems and Networks Department of Electronic Engineering Shanghai Jiaotong University Shanghai China

In this paper, we investigate experimentally an integrated quantum secure communication system using weak coherent state. Two modules are involved in the presented system. One is used for generating the secret key which is obtained using continuous variable quantum key distribution scheme, and the other serves to encrypt and decrypt the real-time private data using a pure quantum cryptographic algorithm. The sifted key rate with reverse reconciliation is 8.6 and 3.9 kb/s in the quantum key distribution scheme under the individual attack and the collective attack, respectively. The system uses an all-fiber dual unbalance beam Mach-Zehnder interferometer, and is implemented with a 500 kb/s modulation rate over 27.2 km of optical fiber.

关键词： quantum key distribution quantum stream encryption integrated system

Coexistence of broadband power line communication systems

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The Journal of china Universities of Posts and Telecommunications 2009年第4期16卷 125-128页

作者： YANG Biao ,L Ying-hua,ZHANG Hong-xin School of electronic engineering,Beijing University of Posts and Telecommunications,Beijing 100876,china School of electronic engineering Beijing University of Posts and Telecommunications Beijing 100876 China

Recent progress in home networks enhances the application of broadband power line communication （BPL） since it does not require any installation of new communication lines or outlets. However, high-density distribution of BPL devices may bring down the access quality. Besides, the electromagnetic field radiating from the power line may cause interference with other radio systems. Thus, the objective of this study is to investigate the impact of cumulative interference in BPL systems, especially focused on indoor environment. A 2-D model describing the BPL transmission activity is proposed. Based on transmission characteristics of the main networks, it takes into account the coexistence effect of the BPL devices. The maximum acceptable density of BPL devices and the radiation field are finally determined.

关键词： BPL coexistence effect radiating electromagnetic field

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Si基Bi_4Ti_3O_(12)铁电薄膜的制备与特性研究

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物理学报 2004年第4期53卷 1265-1270页

作者：王华桂林电子工业学院通信与信息工程系桂林541004

采用sol_gel工艺 ,在分层快速退火的工艺条件下成功地制备了高质量Si基Bi4Ti3O12 铁电薄膜 .研究了Si基Bi4Ti3O12 薄膜的生长行为、铁电性能、C_V特性和疲劳特性 .研究表明 :Si基Bi4Ti3O12 薄膜具有随退火温度升高沿c轴择优生长的趋势 ... 详细信息

采用sol_gel工艺 ,在分层快速退火的工艺条件下成功地制备了高质量Si基Bi4Ti3O12 铁电薄膜 .研究了Si基Bi4Ti3O12 薄膜的生长行为、铁电性能、C_V特性和疲劳特性 .研究表明 :Si基Bi4Ti3O12 薄膜具有随退火温度升高沿c轴择优生长的趋势 ;退火温度通过影响薄膜的晶粒尺寸、生长取向和薄膜中载流子的浓度来改变Si基Bi4Ti3O12 薄膜的铁电性能 ;Ag Bi4Ti3O12 p_Si异质结的C_V特性曲线呈现顺时针回滞 ,可以实现极化存储 ;10 9次极化反转后Bi4Ti3O12 薄膜的剩余极化仅下降 12 % 。

关键词：铁电薄膜钛酸铋退火处理 C-V特性薄膜生长剩余极化率

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Performance of iteratively decoded bit-interleaved coded modulation with chaos based interleaving strategies

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Science china(Information Sciences) 2010年第4期53卷 833-841页

作者： ZOU XueLan1*, LIU WeiYan2 & FENG GuangZeng3 1department of electronic and Information engineering, Zhejiang Institute of Media and communications, Hangzhou 310018, china 2department of Information engineering, Jiangsu City Vocation College, Nanjing 210036, china 3College of communication and Information engineering, Nanjing University of Posts and Telecommunications, Nanjing 210003, china department of electronic and Information engineering Zhejiang Institute of Media and Communications Hangzhou China department of Information engineering Jiangsu City Vocation College Nanjing China College of communication and Information engineering Nanjing University of Posts and Telecommunications Nanjing China

Bit-interleaved coded modulation with iterative decoding (BICM-ID) is a bandwidth efficient trans- mission scheme which is well suitable for next-generation mobile communications. The interleaver design is critical to the high performance of BICM-ID. In this paper we investigate the application of the chaos theory to the interleaver design to further improve the performance of BICM-ID. A new interleaving scheme based on the chaos theory is proposed. Compared with the random interleaver, the proposed approach has the ad- vantages including lower system delay and higher transmission efficiency. Simulation results in both additive white Gaussian noise (AWGN) channel and Rayleigh fading channel are provided, which demonstrates that the new interleaver is better than the random interleaver and exhibits excellent performance when applied to the BICM-ID system.

关键词： chaos interleaving bit-interleaved coded modulation (BICM) iterative decoding