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Nonlinear polarization effects and mitigation in polarization-division-multiplexed coherent transmission systems

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Chinese Optics Letters 2010年第9期8卷 844-851页

作者：谢崇进 bell laboratories Alcatel-Lucent 791 Holmdel-Keyport Road Holmdel NJ 07733 USA

Using numerical simulations, the nonlinear transmission performance of polarization-division-multiplexed quadrature-phase-shift-keying （PDM-QPSK） coherent systems is studied. It is found that inter-channel cross-polarization modulation （XPolM） induced nonlinear polarization scattering can significantly degrade the transmission performance of PDM-QPSK coherent systems and change the perspective of dispersion management in optical coherent transmission systems. Some techniques to mitigate nonlinear polarization scattering in dispersion-managed PDM coherent transmission systems are discussed, including the use of time-interleaved return-to-zero （RZ） PDM formats, the use of periodic-group-delay PGD dispersion compensators, and the judicious addition of some polarization-mode-dispersion （PMD） in the transmission link. It is shown that if nonlinear polarization scattering can be well mitigated, a polarization multiplexed optical coherent transmission system with dispersion management could perform better than that without it.

关键词： QPSK NRZ Nonlinear polarization effects and mitigation in polarization-division-multiplexed coherent transmission systems PDM WDM PGD

Scalable non-mode selective Hermite–Gaussian mode multiplexer based on multi-plane light conversion

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Photonics Research 2021年第2期9卷 88-97页

作者： HE WEN YUANHANG ZHANG RACHEL SAMPSON NICOLAS K.FONTAINE NING WANG SHENGLI FAN GUIFANG LI The College of Optics&Photonics University of Central FloridaOrlandoFlorida 32816-2700USA bell laboratories Alcatel-LucentHolmdelNew Jersey 07733USA

Non-mode-selective(NMS) multiplexers(muxes) are highly desirable for coherent power combining to produce a high-power beam with a shaped profile(wavefront synthesis) from discrete, phase-locked emitters. We propose a design for a multi-plane light conversion(MPLC)-based NMS mux, which requires only a few phase masks for coherently combining hundreds of discrete input beams into an output beam consisting of hundreds of Hermite–Gaussian(HG) modes. The combination of HG modes as a base can further construct a beam with arbitrary wavefront. The low number of phase masks is attributed to the identical zero-crossing structure of the Hadamard-coded input arrays and of the output HG modes, enabling the practicality of such devices. An NMS mux supporting 256 HG modes is designed using only seven phase masks, and achieves an insertion loss of-1.6 d B, mode-dependent loss of 4.7 d B, and average total mode crosstalk of-4.4 d B. Additionally, this design,featuring equal power for all input beams, enables phase-only control in coherent power combining, resulting in significant simplifications and fast convergence compared with phase-and-amplitude control.

关键词： mode coherent hundreds

40 Gbit/s Transparent Network Based on Wavelength-Selective Optical Cross Connect

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光学学报 2003年第S1期23卷 711-712页

作者： Yikai Su bell laboratories, Lucent Technologies, 791 Holmdel-Keyport Rd, Holmdel, New Jersey, USA bell laboratories Lucent Technologies 791 Holmdel-Keyport Rd Holmdel New Jersey USA

This paper discusses a 40-Gbit/s transparent optical network focusing on the optical transport performance. We show 1200-km transmission with two WSOXC' sspaced by 400 km. In addition, network control issues are brief... 详细信息

关键词： GMPLS as in of be WDM Gbit/s Transparent Network Based on Wavelength-Selective Optical Cross Connect EDFA on

A NOVEL MARKOV ANALYTICAL MODEL FOR THE TCP/AQM SYSTEMS

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Journal of Electronics(China) 2010年第1期27卷 15-23页

作者： Cao Zhenzhen Xiao Yang Chi Caixia Institute of Information Science of Beijing Jiaotong University Beijing 100044 China bell-laboratories Research China Beijing 100080 China

A novel closed-loop feedback TCP/AQM(Transfer Control Protocol/Active Queue Management) model is proposed in this paper using a discrete-time Markov chain,and a way to calculate the equilibrium distribution of this model is *** the model,system time is divided into time slots,the bottleneck router queue model and TCP window size model in each slot are ***,by combining adjacent slots,an integrated TCP/AQM analytical model is *** this model,the average values of packets dropping ratio and queue length in the router and TCP sending rate can be estimated,hence,this model could be a useful tool for the analysis of AQMs and support the development of new AQM schemes *** proposed TCP/AQM model is extended to a TCP-UDP(Control User Datagram Protocol)/AQM model,to analyze the TCP/AQM system performance when UDP flows *** implementing this model on Matlab,we compare its solutions to NS2 simulated solutions,then the validity of the model to analyze the closed-loop feedback TCP/RED(Random Early Detection) system is verified.

关键词： Transfer Control Protocol(TCP) Active Queue Management(AQM) Markov chain Congestion control User Datagram Protocol(UDP)

STEINER MINIMAL TREES FOR BAR WAVES

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Acta Mathematicae Applicatae Sinica 1987年第3期3卷 246-256页

作者：堵丁柱黄光明 AT&T bell laboratories Institute of Applied Mathematics Academia Sinica U.S.A. New Jersey 07974 Murray Hill

A Steiner minimal tree (SMT) for a set of points P in the plane is a shortest networkinterconnecting *** construction of a SMT for a general set P is known to be an ***,SMTs have been constructed for special sets P such as ladders,splitting trees,zigzag lines and co-circular *** this paper we study SMTs for a wide class of point-sets calledmild bar *** show that a SMT for a mild bar wave must assume a special form,thus the numberof trees needed to be inspected is greatly *** if a mild bar wave is also a mild rectan-gular wave,then we produce a Steiner tree constructible in linear time whose length can exceed thatof a SMT by an amount bounded by the difference in heights of the two endpoints of the rectangularwave,thus independent of the number of *** a rectangular wave satisfies some otherconditions (including ladders as special cases),then the Steiner tree we produced is indeed a SMT.

关键词： SMT

AUTOMATIC SPEECH RECOGNITION IN MANDARIN FOR EMBEDDED PLATFORMS

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AUTOMATIC SPEECH RECOGNITION IN MANDARIN FOR EMBEDDED PLATFO...

OPTIMAL ASSEMBLY BY MONOTONIC PROPERTY

6～(th) International Conference on Spoken Language Processing

作者： PrabhuRaghavan SunilK.Gupta bell laboratories Lucent Technologies New JerseyUSA bell laboratories Lucent Technologies New JerseyUSA

＜正＞In this paper, we describe a real-time automatic speech recognition system for Mandarin for low-cost embedded platforms using fixed-point digital signal processors. The hands-free, speaker-independent speech recognition system employs 41 mono-phone models for representing the sounds in Mandarin Chinese and 11 whole-word models for connected digit recognition. The system achieves greater than 98％ recognition accuracy on our hands-free test database of 46 distinct command phrases. The system achieves 95.9％ digit accuracy on a 14 speaker, hands-free, connected digit recognition database. The analysis of the results shows that for speakers without dialect, the digit recognition accuracy is almost 98％. We present a detailed analysis of the digit recognition results and propose further improvements. A realtime platform based upon Lucent’s DSP1627 fixed-point digital signal processor has been developed.

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来源： cnki会议评论

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cnki会议

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Systems Science and Mathematical Sciences 1990年第1期3卷 36-45页

作者：堵丁柱 F.K.Hwang Institute of Applied Mathematics Academia SinicaBeijingChina AT&T Bell Laboratories Murray HillNew JerseyU.S.A

Consider a system containing a type of n *** device consists of *** mn parts for n devices with different working probabilities,how do we groupthem into n devices such that the system is most reliable.A monotonic grouping means thatthe best parts are put together,then the best remaining parts are put together,etc..Asufficient and necessary condition for such grouping being optimal will be given in *** an application,we show that the monotonic grouping is optimal for the two-stagek-out-of-n *** m=2,we also study the grouping that the best pairs to the worst,the second best pairs to the second worst,etc.,associated with a redundant device problem.

关键词： Reliability k-out-of-n system optimization monotone assignment

Mirroring Smartphones for Good:A Feasibility Study

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ZTE Communications 2011年第1期9卷 9-14页

作者： Bo Zhao Zhi Xu Caixia Chi Sencun Zhu Guohong Cao Department of Computer Science and Engineering The Pennsylvania State University bell laboratories AlcateI-Lucent Technologies

An increasing number of applications and functions are being *** smartphones, but smartphones have limited computation ability and battery resources. To enhance smartphone capacity, cloud computing and virtualization techniques can be used to shift the workload from smartphone to computational infrastructure. In this paper, we propose a new framework in which a mirror is kept for each smartphone on a computing infrastructure in the telecom network. With mirrors, the workload can be greatly reduced, and smartphone resources can be virtually expanded. The feasibility of deploying this framework in telecom networks is demonstrated in the protocol design, a synchronization study, and a scalability test. Two applications are introduced to show how computational workload on the smartphone and traffic in the telecom network are signiScantly reduced using our techniques.

关键词： mirror cloud computing smartphone

INFORMATION-CENTRIC NETWORKING

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China Communications 2015年第7期12卷 I0002-I0003页

作者： BI Jun Luca Muscariello ZHANG Beichuan Dept.of Computer Science and Technology at Tsinghua University bell laboratories Research and a research scientist at bell Labs USA Network Architecture & IPv6 Research Division Institute for Network Sciences and Cyberspace at Tsinghua University communicationengineering from the Politecnicodi Torino Italy Department of Computer Scienceat the University of Arizona

Information-Centric Networking(ICN)is an emerging direction in Future Internet architecture research,gaining significant tractions among academia and *** to replace the conventional host-to-host communication model by... 详细信息

关键词：网络体系结构通信模型应用程序开发信息中心数据内容内容分发 ICN 牵引力