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Data Matrix Code reconstruction from the image acquired by the Multilayered Waveguide optical Card

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Data Matrix Code reconstruction from the image acquired by t...

2010 Second International Conference on Computational Intelligence and Natural Computing (CINC 2010)

作者： Minfen Gu Analysis and Testing center Nanjing Normal university Nanjing china Zhongcheng Liang College of Optoelectronic Engineering Nanjing university of posts & telecommunications Nanjing china Qingyu Ma School of Physics and Technology Nanjing Normal university Nanjing china

The Data Matrix Code （DMC） recorded by the multilayered waveguide optical card （MWOC） is distorted seriously in the fabrication and readout procedure. Digital image processing is applied to the acquired image from the WMOC to decrease the distortion introduced in the two-dimensional data recoding and reading procedures. In this paper, some digital image processing algorithms are put forward such as with Butterworth Lowpass Filter （BLPF） technique to reduce noise in the frequency domain, with implementing first order digital derivative to the sum profile of the gray-level in the horizontal and vertical lines to trace the contour of the whole DMC from the image to realize image segmentation, with the region filling with 0 or 1 after the calculation of the side size of the code bit and its center coordinate as well as the regions division to satisfy the code bit blocking. With these processing, we can restore the round code point to square shape. And the experimental result shows the feasibilty of the proposed reconstruction methodology and DMC can be decoded correctly and effectively.

关键词： Matrix Data Code Multilayered Waveguide optical Card image processing

Distributed redundant reservation protocol and QoS provisioning in WR-OBS system

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Distributed redundant reservation protocol and QoS provision...

Asia-pacific optical Communications 2004

作者： Zhou LAN Hong xiang GUO Jian WU Jin tong LIN optical Communications center (p.o.box 55) Beijing university of posts and telecommunications Beijing P. R. china 100876

Wavelength Routed optical Burst Switching (WR-OBS) is considered an efficient switching technique in optical networks, especially in the situation of no wavelength converters. A QoS scheme based on ce

关键词： OBS WR-OBS Burst Blocking Probability Distributed Control Protocols

Impact of optical Hop Constraints on the IP/MPLS-over-WSON networks CAPEX

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china Communications 2015年第11期12卷 112-118页

作者： LIU Fengqing Jaume Comellas School of Opto-Electronic Engineering Nanjing University of Posts and Telecommunications Dept.of Signal Theory and Communications Universitat Politècnica de Catalunya Barcelona

In this work,the impact of hop constraints on the CAPEX of multi-layer IP/MPLS over WSON networks is evaluated under different scenarios. By routing lightpaths with different number of transparent hops,the cost of networks varies significantly. This effect is thoroughly analyzed with a heuristic algorithm for different network topologies belonging to some European network operators. The main conclusion extracted is that limiting the transparent reach in such multi-layer networks can give a good tradeoff between CAPEX of IP/MPLS networks and WSON networks,and even lead to signifi cant savings in CAPEX when compared to longer lightpaths routing strategies.

关键词： IP/MPLS over WSON networks optical hop constraints CAPEX heuristics

利用半导体光纤环形激光器实现四波混频可调谐波长变化

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中国激光 2001年第3期28卷 261-264页

作者：迟楠齐江郑远陈树强管克俭北京邮电大学光通信中心北京100876

利用SOA光纤环构成环形激光器 ,对波长为 15 45 1nm的 2 5Gbit/s入射信号进行了四波混频波长变换。采用三级滤波加前置放大器形式成功滤出变换信号 ,向上变换最大距离达 13 8nm。

关键词：半导体光纤环形激光器四波混频全光波长变换可调谐波长变化

Performance and Optimization of 10 Gb/s Electroabsorption Modulator in Short Transmission

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Semiconductor Photonics and Technology 2003年第3期9卷 162-165页

作者： WANG An bin, WU Jian, LIN Jin tong (optical Communication center,Beijing university of posts and Telecommunication,Beijing 100876,CHN) optical Communication center Beijing University of Posts and Telecommunication 北京 100876

Transmission performance of electroabsorption modulator in 10 Gb/s transmission systems has been simulated and analyzed under the condition of taking into account the chirp,extinction ratio, transmissivity and rise/fall *** show that short transmission distance without EDFA after EAM can be used in future metropolitan area network,but the transmissivity must be carefully considered. The sampling time range and decision level can be optimized to reduce the bit error ratio.

关键词： Electroabsorption modulator Transmissivity Sampling time Decision level

research and Design of a Novel Polarization-Maintaining Beam Switch with Isolator Hybrid Component

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Research and Design of a Novel Polarization-Maintaining Beam...

The 2004 Joint Conference of the 10～(th) Asia-Pacific Conference on Communications and the 5～(th) International Symposium on Multi-Dimensional Mobile Communications

作者： Xiaohua Ye Min Zhang Peida Ye Zexiong Zhao(optical Communications center P.O. Box 111# Beijing university of posts and telecommunications Beijing 100876. china: Zhuhai Opiink Communications Inc. FTZ Zhuhai 519030 china)

＜正＞Proposed in this paper is a kind of polarization-maintaining beam switch with isolator hybrid component, which can be used in insertion toss （IL） and extinction ratio （ER） testing for PM related components a...

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一种资源占用统计最小的流分类方法研究

通信学报 2001年第11期22卷 58-63页

作者：邵旭丁伟石晶林北京邮电大学培训中心北京100876

本文通过分析流分类要达到的目标，得到了使边缘标记交换路由器资源占用统计最小的最佳分类门限，从而找到了流分类的科学度量准则。依据该推则和实测Ｉｎｔｅｒｎｅｔ流特性提出一种基于端口的改进Ｘ／Ｙ流分类方法，仿真和分析表明该... 详细信息

本文通过分析流分类要达到的目标，得到了使边缘标记交换路由器资源占用统计最小的最佳分类门限，从而找到了流分类的科学度量准则。依据该推则和实测Ｉｎｔｅｒｎｅｔ流特性提出一种基于端口的改进Ｘ／Ｙ流分类方法，仿真和分析表明该方法较目前其它的数据驱动分类方法更加科学和完善。

关键词：因特网流分类通信协议网络互连协议交换

Nonlinear Prediction with Deep Recurrent Neural networks for Non-Blind Audio Bandwidth Extension

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china Communications 2018年第4期15卷 72-85页

作者： Lin Jiang Ruimin Hu Xiaochen Wang Weiping Tu Maosheng Zhang National Engineering research center for Multimedia Software School of Computer Science Wuhan University Wuhan 430072 China Institute of Big Data and internet Innovation Hunan University of Commerce Changsha 410205 China Software College East China University of Technology Nanchang 330013 China Collaborative Innovation center for Economics crime investigation and prevention technology Jiangxi Province Nanchang 330103China Hubei Key Laboratory of Multimedia and Network Communication Engineering Wuhan University Wuhan 430072 China Collaborative Innovation center of Geospatial Technology Wuhan 430079 China

Non-blind audio bandwidth extension is a standard technique within contemporary audio codecs to efficiently code audio signals at low bitrates. In existing methods, in most cases high frequencies signal is usually generated by a duplication of the corresponding low frequencies and some parameters of high frequencies. However, the perception quality of coding will significantly degrade if the correlation between high frequencies and low frequencies becomes weak. In this paper, we quantitatively analyse the correlation via computing mutual information value. The analysis results show the correlation also exists in low frequency signal of the context dependent frames besides the current frame. In order to improve the perception quality of coding, we propose a novel method of high frequency coarse spectrum generation to improve the conventional replication method. In the proposed method, the coarse high frequency spectrums are generated by a nonlinear mapping model using deep recurrent neural network. The experiments confirm that the proposed method shows better performance than the reference methods.

关键词： audio coding non-blind audiobandwidth extension context correlation deeprecurrent neural network

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基于频谱分割的光码分多址接入系统实验研究

中国激光 2003年第1期30卷 41-44页

作者：左超马文华高屹然周光涛伍剑林金桐北京邮电大学光通信中心北京100876

利用频谱分割技术进行了光码分多址接入 (OCDMA)系统传输实验。该实验的编解码器利用可调谐法珀腔的不同自由谱域来区分不同用户 ,分析、测量了多址干扰对系统性能的影响 ,对系统中的光源、信道和编解码器的特性进行了讨论。测试表明 ... 详细信息

利用频谱分割技术进行了光码分多址接入 (OCDMA)系统传输实验。该实验的编解码器利用可调谐法珀腔的不同自由谱域来区分不同用户 ,分析、测量了多址干扰对系统性能的影响 ,对系统中的光源、信道和编解码器的特性进行了讨论。测试表明 ,该接入系统在速率为 15 5Mb s ,MAI值是接收用户光功率 30倍的情况下 ,传输 11km普通单模光纤后 ,误码率优于 10 - 9。该系统实现简单 ,成本低 ,是全光接入的可选方案。

关键词：光码分多址接入光纤通信技术频谱分割全光接入 OCDMA