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2009 9th Topical Meeting on Silicon Monolithic Integrated Circuits in RF System, SiRF'09

作者： Zhu, Yunliang Hu, Jianyun Wu, Hui Laboratory for Advanced Integrated Circuits and Systems Department of Electrical and Computer Engineering University of Rochester Rochester NY United States

ISBN: (纸本)9781424428311

In this paper, we present a fully-integrated impulse radio UWB transmitter based on a newly-developed ultrafast pulse circuit technique, distributed waveform generator (DWG). A DWG time-interleaves multiple digital pulse generators, and then combines all generated pulses using a wideband on-chip transmission line. A DWG is low power and fully reconfigurable compared to other UWB pulse generation and shaping solutions. It also facilitates the implementation of digital modulation schemes such as on-off keying (OOK) and pulse position modulation (PPM) in the transmitter. A chip prototype with a 10-tap, 10 GS/s dual-polarity DWG was designed and implemented in 0.18m standard digital CMOS. The transmitter's pulse rate can be varied from 16 MHz to 2.5 GHz with an energy efficiency of 25 pJ/pulse. The transmitted pulses with OOK and PPM modulation are successfully demonstrated using 32 Mb/s PRBS data. © 2009 IEEE.

关键词： Amplitude shift keying

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Channel estimation for pilot-aided OFDM systems in single frequency network

Channel estimation for pilot-aided OFDM systems in single fr...

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2009 15th Asia-Pacific Conference on Communications, APCC 2009

作者： Wu, Yiling Zhao, Yuping Li, Dou State Key Laboratory of Advanced Optical Communication Systems and Networks School of Electronics Engineering and Computer Science Peking University Beijing 100871 China

ISBN: (纸本)9781424447855

In single frequency network (SFN), there exist some special long delay spread channels as well as conventional multi-path channels. For pilot-aided orthogonal frequency division multiplex (OFDM) systems, channel estimation is usually accomplished by interpolation with pilots. However, few pilot subcarriers exist within coherent bandwidth under the long delay spread channels in SFN. In this case, conventional interpolation methods cannot work properly. This paper proposes a sinewave based frequency domain interpolation method for channel estimation of pilot-aided OFDM systems in SFN. As simulation results show, the proposed method gives accurate channel estimation under the long delay spread channels, whereas the mismatched wiener interpolation filter (WIF) estimates channel response inaccurately. Moreover, the proposed method performs well under conventional multi-path channels, especially for systems which adopt high order modulations. ©2009 IEEE.

关键词： Channel estimation

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The negative refraction of the 2D triangular lattice of air hole in silicon

The negative refraction of the 2D triangular lattice of air ...

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Photonics and Optoelectronics Meetings (POEM) 2009 - Optoelectronic Devices and Integration

作者： Wu, Chaojun Wu, Jun Hong, Tingting Li, Yanping Wang, Ziyu State Key Laboratory on Advanced Optical Communication Systems and Networks School of Electronics Engineering and Computer Science Peking University Beijing 100871 China

ISBN: (纸本)9780819479051

We study numerically the focusing effects when a Gaussian beam pass through a two-dimensional photonic crystal consisting of triangular structure of air holes. By using plane wave expansion (PWE) and finite difference time domain (FDTD) methods, we find the width of convergent beam is about 2m. Meanwhile, the focusing effects also are influenced by the Gaussian half-width, the numbers of the layers and the incident angle. The structure can be used for light-coupling and near-field scan image application. © 2009 Copyright SPIE - The International Society for Optical engineering.

关键词： Photonic crystals

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A modified Q-parameter anti-collision scheme for RFID systems

A modified Q-parameter anti-collision scheme for RFID system...

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2009 International Conference on Ultra Modern Telecommunications and Workshops

作者： Yinghua, Cui Yuping, Zhao State Key Laboratory of Advanced Optical Communication Systems and Networks School of Electronics Engineering and Computer Science Peking University Beijing 100871 China

ISBN: (纸本)9781424439416

EPC Q scheme is a very popular protocol in RFID, in which the reader uses parameter Q to vary the slot number that tags can select. In this paper, we propose a new algorithm based on this scheme. We first propose a fast and efficient tag estimation method according to stochastic analyses on the first three slots of each frame, then propose a new ALOHA based multi-branch anti-collision scheme. Both theoretical analysis and simulation results indicate the proposed scheme can improve a lot than the standard EPC Q algorithm and the modification is slight. ©2009 IEEE.

关键词： Stochastic systems

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Plasmonic Corrugated Horn Structure for Optical Transmission Enhancement

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Chinese Physics Letters 2009年第12期26卷 122-124页

作者：李光元蔡琳肖峰徐安士 State Key Laboratory of Advanced Optical Communication Systems and Networks School of Electronic Engineering and Computer Science Peking University Beijing 100871 Centre of Excellence for MicroPhotonic Systems (COMPS) Electron Science Research Institute Edith Cowan University 270 Joondalup Drive Joondalup WA 6027 Australia

We propose and theoretically analyze a plasmonic corrugated horn structure for enhanced optical transmission. It makes use of the enhancement of unidirectional propagating surface plasmon polaritons at oblique incidence. Geometric parameters such as the groove depth and width are optimized. Analysis shows that it presents a better performance than the bull＇s eye structure for a small number of grooves.

关键词： Chinese climate network complex systems small world community

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User-level virtual network support for sky computing

User-level virtual network support for sky computing

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5th IEEE International Conference on e-Science, e-Science 2009

作者： Tsugawa, Maurício Matsunaga, Andréa Fortes, José Advanced Computing and Information Systems Laboratory Department of Electrical and Computer Engineering University of Florida PO Box 116200 Gainesville FL 32611-6200 United States

ISBN: (纸本)9780769538778

With the emergence of multiple cloud providers of Infrastructure-as-a- Service, it becomes possible to envision a near-future when high-performance computing users could combine services from different clouds to access huge numbers of resources. However, as more administrative privileges are exposed to end users, providers are required to deploy network security measures that present challenges to the network virtualization technologies that are needed to enable inter-cloud communication. This paper studies these challenges and proposes techniques to enable unmodified applications on resources across distinct clouds. The techniques are implemented in TinyViNe, an extension to ViNe, a virtual networking technology for distributed resources in different administrative domains. The results of evaluating TinyViNe on a WAN-based testbed across three sites are reported for a bioinformatics application (BLAST) and MPI benchmarks. The results confirm that TinyViNe enables cross-cloud computing while having little impact on application performance. TinyViNe also has auto-configuration and "download-and-run" capabilities for easy deployment by users who are not knowledgeable about networking. © 2009 IEEE.

关键词： Virtualization

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Tunable group velocity of light propagation and its application

Tunable group velocity of light propagation and its applicat...

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2009 Symposium on Photonics and Optoelectronics, SOPO 2009

作者： Yonglan, Hou Chao, Peng Lei, Jia Lixin, Zhu Zhengbin, Li State Key Laboratory of Advanced Optical Communication Systems and Networks School of Electronics Engineering and Computer Science Peking University Beijing China State Key Joint Laboratory of Integrated Optoelectronics Beijing China

ISBN: (纸本)9781424444113

In this paper, we proposed a novel approach to demonstrate optically controllable pulse group velocity at telecommunication wavelengths in EDF due to CPO. First we reviewed recent advances in slow-light-based optical signal processing, then we study slow and fast light propagation in erbium doped fiber abstractly based on theory and simulation model. It is revealed though the research that the time delay and advancement depends greatly on the pump power, influence of the ion density on the group velocity of light propagation is also studied. Based on our discussion, the optimization parameters should be selected in order to obtain more appropriate time delay and the slowdown of group velocity, which is of great importance to the communication industry. ©2009 IEEE.

关键词： Light velocity

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A differentiated QoS aware multipath routing algorithm for optical burst switched networks

A differentiated QoS aware multipath routing algorithm for o...

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Network Architectures, Management, and Applications VII

作者： Chi, Yuan Zhang, Zhenrong Li, Zhengbin Anshi, Xu State Key Laboratory of Advanced Optical Communication Systems and Networks School of Electronics Engineering and Computer Science Peking University Beijing China School of Computer Electronics and Information Guangxi University Nanning Guangxi China

ISBN: (纸本)9780819480354

Optical burst switching (OBS) is thought to be the best way to adapt the bursty IP traffic over optical WDM networks. It provides statistical multiplexing gains and avoids long end to end setup time of traditional virtual circuit configuration. However, under the current and foreseeable limitations of optical technology, performance of OBS is mainly hampered at network nodes by burst contention. The contention is serious constraints on the capacity of OBS networks. A leading source of contention is the congestion at congested links where a limited number of wavelengths are shared by a lot of bursts. These congested links are stemming from burst routing algorithms. In this paper, we studied on routing path competition phenomenon. We proposed a differentiated QoS aware multipath routing algorithm for OBS networks. This algorithm is evaluated through extensive numerical studies over a typical topology--the 14-node NSFnet. Results show that it outperforms the existing algorithms in terms of burst blocking probability and link utilization. © 2009 SPIE-OSA-IEEE.

关键词： Optical burst switching

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A novel ellipse model for optically injection-locked VCSELs

A novel ellipse model for optically injection-locked VCSELs

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Frontiers in Optics, FiO 2009

作者： Guo, Peng Yang, Weijian Parekh, Devang Chang-Hasnain, Connie J. Department of Electrical Engineering and Computer Sciences University of California Berkeley CA 94720 United States State Key Laboratory of Advanced Optical Communication Systems and Networks School of Electronics Engineering and Computer Science Peking University Beijing 100871 China

A novel ellipse graphic tool is established based on injection-locked rate equations to analyze the cavity mode behavior of injection-locked vertical-cavity surface-emitting lasers. Calculation based on this model sho... 详细信息

ISBN: (纸本)9781557528780

关键词： Surface emitting lasers

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A bias free, quantum random number generator

A bias free, quantum random number generator

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Frontiers in Optics, FiO 2009

作者： Wei, Wei Guo, Hong CREAM Group State Key Laboratory of Advanced Optical Communication Systems and Networks Institute of Quantum Electronics School of Electronics Engineering and Computer Science Peking University Beijing 100871 China

Based on the random photon emission of laser diode, we propose a new approach for true random number generation with convenient implementation, which is intrinsically bias free and suitable for high speed applications... 详细信息

ISBN: (纸本)9781557528780

关键词： Random number generation

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