检索结果-内蒙古大学图书馆

optical coding scheme for all-optical analog-to-digital conversion using asymmetrical Y-branch waveguide

OPTICS COMMUNICATIONS 2011年第9期284卷 2298-2302页

作者： Tang, Xionggui Liao, Jinkun Lu, Rongguo Li, Heping Zhang, Xiaoxia Zhang, Lin Liu, Yongzhi Univ Elect Sci & Technol China Sch Optoelect Informat Chengdu 610054 Peoples R China

The novel optical coding scheme for all-optical analog-to-digital conversion has been proposed, in which asymmetrical Y-branch waveguide structures have been introduced to achieve the desired optical power splitting. The optical performance has been simulated by using finite-difference beam propagation method (FD-BPM), which shows that the designed component exhibits good coding performance. Experimentally, the optical coding component has been fabricated and measured. The optical power contrast between bit code 1 and Oat output port is more than 37 dB, and measured imbalance of output power is less than 1.5 dB for bit code 1. (C) 2011 Elsevier B.V. All rights reserved.

关键词： optical coding All-optical analog-to-digital conversion Asymmetrical Y-branch waveguide

来源：评论

学校读者我要写书评

暂无评论

Temperature-Robust Monitoring of TDM-PONs Through optical coding Assisted by Broadband λ-Tunable I-OFDR

引用

JOURNAL OF LIGHTWAVE TECHNOLOGY 2021年第14期39卷 4607-4613页

作者： Fernandez, Manuel P. Morbidel, Leonardo Bulus-Rossini, Laureano A. Costanzo-Caso, Pablo A. CNEA Lab Invest Aplicada Telecomunicac LIAT DIT GDTyPEGAIyANN RA-8400 San Carlos De Bariloche Rio Negro Argentina Inst Balseiro RA-9500 San Carlos De Bariloche Rio Negro Argentina

We present a technique for remote monitoring of time-division multiplexed passive optical networks (TDM-PONs) based on fiber Bragg grating (FBG) encoders interrogated by a broadband incoherent optical frequency-domain reflectometer (I-OFDR). Compared with previous approaches, the proposed system features inherent high robustness against temperature-induced wavelength shifts in the FBG-encoders. The I-OFDR-based monitoring unit enables measurements with high resolutions and sensitivities without the need for high peak-power monitoring signals, which minimizes its footprint on the data links. We carry out a comprehensive description of the system and we evaluate its capacity in terms of signal-to-interference ratio (SIR). We show that, through suitable windowing, a SIR >= 20 dB can be achieved in highly-dense TDM-PONs having more than 128 customers through the use of moderate measurement bandwidths of 300 MHz. We experimentally demonstrate the proposal in a TDM-PON carrying a 10 Gbps downstream data signals, obtaining a negligible impact in the downlink performance, such as the bit error rate remains below 10(-6).

关键词： Passive optical networks monitoring optical coding optical frequency-domain reflectometry

来源：评论

学校读者我要写书评

暂无评论

Fluorescent magnetic emulsion droplets: Potential material for multiplexed optical coding of biomolecules

引用

JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS 2007年第1期311卷 88-91页

作者： Mandal, Swapan K. Visva Bharati Univ Dept Phys Santini Ketan 731235 W Bengal India

Fluorescent magnetic microbeads can be potentially used in optical coding of biomolecules. The currently commercially available microbeads so far suffer polydispersity in both size and fluorescence intensity. Large statistical fluctuations in intensity level are quite detrimental for their use in optical coding applications. To optimize them for multiplexed optical coding of biological molecules, besides monodispersity, statistical fluctuations in intensity of beads need to be maintained as low as possible (< 1 % and less) in order to obtain a large number of codes. Here, we show that fluorescent and magnetic droplets synthesized through a simple and elegant oil-in-water microemulsion technique can have statistical fluctuations as low as < 1 % with a number of fluorescent labels. (C) 2006 Elsevier B.V. All rights reserved.

关键词： magnetic droplet emulsion optical coding fluorescence

来源：评论

学校读者我要写书评

暂无评论

Design and Performance Evalauation of an optical coding Scheme for PON Monitoring 16

Design and Performance Evalauation of an Optical Coding Sche...

引用

16th Workshop on Information Processing and Control (RPIC)

作者： Fernandez, Manuel P. Caso, Pablo A. Costanzo Rossini, Laureano A. Bulus UNCuyo Inst Balseiro CNEA Ave Bustillo 9500 Barioche RN Argentina

ISBN: (纸本)9781467384667

optical coding has numerous properties that make its application to remote monitoring and failure detection in passive optical networks very attractive. Several approaches for encoder implementation have been proposed. One of them consist of a couple of fiber Bragg gratings forming a cavity producing multi-level periodic codes. In this work we propose and evaluate the performance of two new encoder schemes based on this premise. These new encoders generate codes with Hamming weight 2 and 3 in order to improve the performance of multi-level periodic codes. We observe that the proposed coding schemes show a better performance under certain scenarios.

关键词： passive optical networks monitoring optical coding OCDMA

来源：评论

学校读者我要写书评

暂无评论

Method of digital hologram synthesis for hidden image optical coding in holographic security devices

Method of digital hologram synthesis for hidden image optica...

引用

Conference on Speckles, From Grains to Flowers

作者： Lymarenko, Ruslan Budnyk, Oksana Natl Acad Sci Ukraine Int Ctr Inst Appl Opt 10-G Kudryavska Str UA-04053 Kiev Ukraine

ISBN: (纸本)0819464260

The methods of increase the protective properties of holographic elements by using hidden image are discussed. The extension of the new method of wave equation solution is useful for providing analytical studying and numerical modeling of diffraction on amplitude-phase discrete mask. Possibilities of its practical application for structured light beam generation and wavefront reconstruction is considered. Conclusions regarding the possibilities of the representation of the arbitrary fields by using the discrete matrix of elementary diffractive aperture cells for an enhancement of the iteration algorithm of hologram synthesis are obtained. The method proposed of computer-generated holograms (CGH) synthesis enables one to synthesize CGH's and to simulate the digital image processing techniques for hidden image coding. The further improvement of this approach of coding amplitude-phase masks for both recording and reading of hidden image by holographic security devices is proposed. By using coding phase mask with quasi-stochastic distribution for diffraction pattern writing as additional structure on the protective hologram are explained. It is shown that computer generated hologram (CGH) can restore spatial structure represented by optical singularities. The conditions of reconstruction of the hidden image are discussed in case of encoding and decoding masks are not coinciding. A structure of a system that looks promising to produce a like hologram and method of operation directly images a pattern, which is previously calculated by computer and displayed on the amplitude-phase mask is explained. The results obtained by numerical and experimental means are accompanied with a discussion about extents of this method.

关键词： optical coding hidden image holographic security device

来源：评论

学校读者我要写书评

暂无评论

A New Method for Monitoring GPON Based on optical coding

A New Method for Monitoring GPON Based on Optical Coding

引用

International Telecommunication Networks and Applications Conference

作者： Huda Saleh Abbas Mark A. Gregory RMIT University

ISBN: (纸本)9781467393492

Monitoring Passive optical Networks (PON) based on optical coding (OC) is a cost-effective monitoring technique. In a PON, the monitoring signals are transmitted on a dedicated band (U band) with data transmitted using a different band (L-band). This paper introduces a new method to monitor Gigabit Passive optical Networks based on an OC technique. The proposed method utilizes the information from the PON ranging process that is managed by the optical Line Terminal to specify a fixed delay time for transmissions to and from the optical Network Units. The paper shows that information about the link status can be extracted from the decoded signal.

关键词： GPON Monitoring optical coding Prime Code Ranging

来源：评论

学校读者我要写书评

暂无评论

Spectral coding for secure optical communications using refractive index dispersion

引用

OPTICS COMMUNICATIONS 1997年第1-6期133卷 87-92页

作者： Mazurenko, YT Giust, R Goedgebuer, JP SI VAVILOV STATE OPT INST ST PETERSBURG 199034RUSSIA

We demonstrate spectral coding in communication systems based on the use of refractive index dispersion of transparent optical materials. This approach to spectral coding is extremely simple and cheap and allows fibre... 详细信息

关键词： optical coding optical communications dispersion secure communication

来源：评论

学校读者我要写书评

暂无评论

Experimental demonstration of the (de)coding of hybrid phase and frequency codes using a pseudolocal oscillator for optical code division multiplexing

引用

IEEE PHOTONICS TECHNOLOGY LETTERS 1998年第6期10卷 887-889页

作者： Andonovic, I Sotobayashi, H Wada, N Kitayama, KI Univ Strathclyde Dept Elect & Elect Engn Div Optoelect Glasgow G1 1XW Lanark Scotland Lightwave Network Sect Minist Posts & Telecommun Commun Res Lab Koganei Tokyo 184 Japan

This letter details an initial experimental demonstration of (de)coding of optical sequences coded in the two-dimensions of phase and wavelength through a pseudolocal oscillator. Narrow pulses at 1 Gb/s originating from a super-continuum (SC) fiber source with a specific frequency variation across their temporal width were, in addition, phase coded producing hybrid optical sequences. Successful decoding of the sequences using a pseudolocal oscillator in tandem with a coupler and balanced detector (coherent decoding) was accomplished. This approach to code formation allows access to a larger family of codes, potentially permitting more flexible network implementations based on optical code division principles.

关键词： coherent decoding hybrid optical sequences optical code-division multiple-access optical coding

来源：评论

学校读者我要写书评

暂无评论

All-optical analog-to-digital conversion system with a spatial coding method using designed filter

引用

optical REVIEW 2009年第2期16卷 184-187页

作者： Kato, Takuya Konishi, Tsuyoshi Nishitani, Takashi Itoh, Kazuyoshi Osaka Univ Grad Sch Engn Suita Osaka 5650871 Japan

We propose and demonstrate an all-optical analog-to-digital conversion system with a spatial coding method using a designed filter. To make available codes more flexible, the design technique for a computer-generated hologram is introduced to our spatial coding scheme. By designing the spatial coding filter appropriately, this coding scheme enables us to output various digital signals as spatial patterns. By combining this coding method with the optical quantization method using soliton self-frequency shifting in a fiber, the proposed system converts analog sampled signals into arbitrary digital signals. Preliminary experimental results show that 3-bit Gray codes are successfully output as spatial patterns using the designed spatial coding filter.

关键词： optical signal processing optical analog-to-digital conversion optical coding computer-generated hologram (CGH) nonlinear fiber optics free space optics soliton self-frequency shift (SSFS)

来源：评论

学校读者我要写书评

暂无评论

All-optical analog-to-digital conversion using optical interconnection for gray code coding

All-optical analog-to-digital conversion using optical inter...

引用

Conference on optical Transmission, Switching, and Subsystems IV

作者： Nishitani, Takashi Konishi, Tsuyoshi Itoh, Kazuyoshi Osaka Univ Grad Sch Engn 2-1 Yamadaoka Suita Osaka 5650871 Japan

ISBN: (纸本)0819464481

The gray code based all-optical analog-to-digital conversion (ADC) using optical interconnection is described. Recent tremendous growths of optical communications and digital signal processing have encouraged the demand of high-speed and high-resolution ADC. To pursue a high-speed and high-resolution ADC, optical approaches have attracted much attention recently. ADC generally consists of three procedures: sampling, quantization and coding. Whereas the optical sampling techniques have been proposed and realized, the optical quantization and coding techniques have investigated depending on various applications. For the application to the binary detection of a high-speed digital signal, we previously proposed an all-optical ADC which consists of optical quantization using self-frequency shifting in a fiber and optical coding using optical interconnection for general binary code. In addition, since we can easily prepare optical interconnection patterns corresponding to the various codes, this technique can be used in any coding schemes. In this paper, we demonstrate the gray code based all-optical ADC to verify its scalability. Experimental results show that the 8-levels analog signals can be successfully converted into the bitwise allocated 3-bit gray code.

关键词： all-optical analog to digital conversion self-frequency shift ultra-short pulse optical quantization optical coding

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：