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Chinese Physics B 2013年第12期22卷 256-261页

作者：刘道亚罗孝阳刘锦景董建峰 institute of optical fiber communication and network technology Ningbo University

Just like an electronic diode that allows the electrical current to flow in one direction only, a kind of chiral metamaterial structure with a similar functionality for the electromagnetic wave is proposed. The designed nanostructure that consists of twisted metallic split-ring resonators on both sides of a dielectric substrate achieves asymmetric transmission for a forward and backward propagating linearly polarized wave by numerical simulation in near-infrared band. Difference in transmission efficiency of the optimized structure between the same polarized waves incident from opposite directions can reach a maximum at the communication wavelength （1.55 μm）. Moreover, the simulation results of this structure also exhibit strong optical activity and circular dichroism.

关键词： asymmetric transmission optical activity linearly polarized wave circular dichroism

Guided modes in the chiral negative refractive index fiber

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Chinese Optics Letters 2010年第11期8卷 1032-1036页

作者：董建峰李杰 institute of optical fiber communication and network technology Ningbo University

The novel characteristics of guided modes in the chiral negative refractive index fiber are investigated theoretically in this *** derive the characteristic equation of guided *** on two types of chiral metamaterial parameters,we present the dispersion curves,energy flux,and power of guided *** abnormal features,such as the existence of surface mode and dispersion curves with different shapes,intersection of dispersion curves of different guided modes,negative energy flux in the achiral cladding,and zero power at some normalized frequencies,are found in the chiral negative refractive index fiber.

关键词： Dispersion (waves) Guided electromagnetic wave propagation Light refraction Metamaterials Refractometers

Negative refractive index in non-resonance spectrum area

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Chinese Optics Letters 2010年第11期8卷 1067-1070页

作者：徐超董建峰 institute of optical fiber communication and network technology Ningbo University

A new concept to realize negative refractive index in non-resonance spectrum using chiral metamaterial is proposed.A low-index metamaterial is added to diminish the effective refractive index of the combined *** and material parameter retrieval procedures are carried out to determine material *** show evidence of negative refractive index and strong optical activity in the new chiral metamaterial.

关键词： Light refraction Metamaterials Refractometers Surface plasmon resonance

Reflection and transmission of electromagnetic waves on the interface of uniaxial chiral media

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Optoelectronics Letters 2013年第2期9卷 148-152页

作者：董建峰罗孝阳李杰 institute of optical fiber communication and network technology Ningbo University

The reflection and transmission properties of plane waves on the interface of uniaxial chiral media with the optical axis parallel to the interface are investigated. The formulas of the reflected and transmitted power are derived. The curves of the group refractive angles, power of the reflected and transmitted waves for TE and TM incident waves are presented for three cases of dielectric constant combinations and for non-chiral, weak chiral and strong chiral media. Some new results are obtained, which are different from those in the uniaxial chiral media with the optical axis per-pendicular to the interface.

关键词：手征介质透射特性反射波界面单轴电磁波发射功率介电常数

A load balancing multi-path routing scheme based on effective voids for optical burst switching networks

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Science China(Information Sciences) 2015年第2期58卷 131-139页

作者： HUANG Sheng ZHANG YunShui SUN Li Qin YANG XiaoLong LONG KePing Key Laboratory of optical fiber communication technology Chongqing University of Posts and Telecommunications

Multi-path routing in the optical burst switching(OBS) networks can reduce the burst loss probability(BLP) by distributing the data burst traffic to multiple paths, compared with single path routing. Unlike the other multi-path routing schemes without considering the carrying capability of the routes, a new multi-path routing scheme based on effective voids(MPEV) is proposed to balance the load of multi-path and reduce the BLP in the paper. MPEV scheme first obtains the information on effective voids of the bottleneck link of multipath by sending a probe packet periodically. The effective voids can accommodate data bursts and accurately represent the available channel resource that is the main determinant of the BLP for OBS networks without optical random access memory. Then MPEV scheme distributes the burst traffic between an ingress node and an egress node to multiple link-disjoint paths by the ratio of the effective voids. More traffic is distributed to the path that has more effective voids, and vice versa. And the distributed amount is proportional to the effective voids of the bottleneck link. So MPEV scheme can balance the load of multi-path routes and can effectively reduce the BLP by avoiding the high load of a single path. And it is easy to implement and agilely adapt to dynamic network traffic. The performance of MPEV scheme is analyzed by queuing theory and is evaluated by simulation. The numerical results show that the proposed scheme can effectively reduce the BLP and balance the traffic load over multiple paths at the same time.

关键词： optical burst switching multi-path routing effective voids bottleneck link balance traffic load

Research on Radiation Characteristics of Polymeric Plastic fiber

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High technology Letters 2001年第2期7卷 24-26页

作者：殷宗敏 Li Rongyu Ge Wenping Liu Rui National Laboratory on Local fiber-optic communication networks Advanced optical communication System Institute of Optical Fiber Technology Shanghai Jiaotong University

The anti-radiation mechanism of polymeric plastic fiber is analyzed. The radiation characteristic of this type fiber is studied. Our experimental results indicate that under the low radiation dosage (below 1 kGy) the plastic optical fiber’s transmission rate rises instead of descends while this type of fiber is radiated by γ ray, electron beam and proton beam respectively. After a period of time, it gradually reaches a constant value. But under the high radiation dosage (above 1 kGy) the fiber’s transmission rate descends after radiation. Later, it gradually goes up to a constant value.

关键词： Polymer Plastic optical fiber Radiation

Reflection and transmission at the surface of a chiral negative refractive medium

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Optoelectronics Letters 2007年第6期3卷 462-465页

作者： LIU Bln DONG Jian-feng institute of optical fiber communication and network technology Ningbo University Ningbo 315211 China

Electromagnetic fields at the surface of a chiral negative refraction medium (the chirality parameter is larger than the refractive index) are analyzed theoretically. For obtaining chirality parameter,the normalized reflected and transmitted powers as a function of the incident angle are given for the perpendicular (TE) and parallel (TM) polarized incident wave. Brewster angle and total internal reflection angle are discussed. Due to the negative refraction of one eigen-wave in the chiral medium, the reflection, transmission and Brewster angle characteristics are very different from those in the normal chiral medium.

关键词：特种结构材料手性折射反射

Physical Layer Encryption of OFDM-PON Based on Quantum Noise Stream Cipher with Polar Code

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China communications 2024年第3期21卷 174-188页

作者： Xu Yinbo Gao Mingyi Zhu Huaqing Chen Bowen Xiang Lian Shen Gangxiang Jiangsu Engineering Research Center of Novel optical fiber technology and communication network Suzhou Key Laboratory of Advanced Optical Communication Network Technologythe School of Electronic and Information EngineeringSoochow UniversityNo.1 Shizi StreetSuzhou 215006China

Orthogonal frequency division multiplexing passive optical network(OFDM-PON) has superior anti-dispersion property to operate in the C-band of fiber for increased optical power budget. However,the downlink broadcast exposes the physical layer vulnerable to the threat of illegal eavesdropping. Quantum noise stream cipher(QNSC) is a classic physical layer encryption method and well compatible with the OFDM-PON. Meanwhile, it is indispensable to exploit forward error correction(FEC) to control errors in data transmission. However, when QNSC and FEC are jointly coded, the redundant information becomes heavier and thus the code rate of the transmitted signal will be largely reduced. In this work, we propose a physical layer encryption scheme based on polar-code-assisted QNSC. In order to improve the code rate and security of the transmitted signal, we exploit chaotic sequences to yield the redundant bits and utilize the redundant information of the polar code to generate the higher-order encrypted signal in the QNSC scheme with the operation of the *** experimentally demonstrate the encrypted 16/64-QAM, 16/256-QAM, 16/1024-QAM, 16/4096-QAM QNSC signals transmitted over 30-km standard single mode fiber. For the transmitted 16/4096-QAM QNSC signal, compared with the conventional QNSC method, the proposed method increases the code rate from 0.1 to 0.32 with enhanced security.

关键词： physical layer encryption polar code quantum noise stream cipher

Generation of tunable multi-wavelength optical short pulses using self-seeded Fabry-Perot laser diode and tilted multimode fiber Bragg grating

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Chinese Optics Letters 2011年第4期9卷 48-51页

作者：蔡同健刘云启张小贝王廷云 Key Lab of Specialty fiber Optics and optical Access network School of Communication and Information EngineeringShanghai University

We experimentally demonstrate the simultaneous generation of tunable multi-wavelength picosecond laser pulses using a self-seeding configuration that consists of a gain-switched Fabry-Perot laser diode （FPLD） with an external cavity formed by a tilted multimode fiber Bragg grating. Dual- and triple-wavelength pulses are obtained and tuned in a flexible manner by changing the temperature of the FPLD. The side mode suppression ratio larger than 25 dB is achieved at different dual- and triple-wavelengths and the typical pulsewidth of the output pulses is ,-70 ps. In the experiment, the wavelength separation can be narrowed to 0.57 nm.

关键词： Fabry Perot interferometers fiber Bragg gratings fiber optic components fiber optic sensors Multimode fibers

A new burst assembly technique for supporting QoS in optical burst switching networks

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Chinese Optics Letters 2003年第5期1卷 266-268页

作者：阳小龙党明瑞毛幼菊李乐民 National Lab of Broadband optical fiber Transmission and communication networks University of Electronic Science and TechnologyChengdu 610054 Optical Communication InstituteChongqing University of Posts & Telecommunications Chongqing 400065 optical communication institute Chongqing University of Posts & Telecommunications Chongqing 400065 National Lab of Broadband Opticak fiber Transmission and communication networks University of Electronic Science and TechnologyChengdu 610054

This letter proposes a new burst assembly technique for supporting QoS in optical burst switching (OBS) networks. It consists of the adaptive-threshold burst assembly mechanism and QoS-based random offset-time scheme. The assembly mechanism, which is fit well to multi-class burst assembly, not only matches with IP QoS mechanism based on packet classification, and also utilizes fairly and efficiently assembly capacity. Based on token-bucket model and burst segment selective discard (BSSD), the offset-time scheme can smooth the traffic to support OBS QoS. The simulation results show that the technique can improve the performance in terms of packet loss probability (PLP).

关键词： QoS it as A new burst assembly technique for supporting QoS in optical burst switching networks PLP in for