Cost Evaluation of Optical Packet Switches Equipped With Limited-Range and Full-Range Converters for Contention Resolution

Two architectures are proposed for a wavelength-division multiplexed optical packet switch equipped with both limited-range wavelength converters (LRWCs) and shared full-range wavelength converters (FRWCs). The FRWCs are used to overcome the performance degradation in terms of packet loss probability due to the use of LRWCs only. Two different sharing strategies of the FRWCs are considered. In the first architecture, a pool of FRWCs is shared among the arriving packets. In the second one, the sharing is only partial and the packets directed to the same output share a same pool of FRWCs. A probabilistic model is proposed to dimension the number of shared FRWCs so that the same packet loss probability of a switch equipped with only shared FRWCs is guaranteed. After introducing a cost model of the converters depending on the conversion range, we show that the architectures may allow a conversion cost savings on the order of 90%.     

Contention Resolution for Burst-Mode Traffic Using Integrated SOA-MZI Gate Arrays and Self-Resetting Optical Flip-Flops

We demonstrate a photonic routing system that resolves the contention between bursty optical packets. The circuit is realized exclusively with integrated photonic components through the interconnection of semiconductor optical amplifier Mach–Zehnder interferometers gate arrays and optical flip-flops. The system resolves the contention—without burst segmentation—in the wavelength domain with a low power penalty ( $≪ $1 dB).      

光分组交换网络的冲突解决：用光纤延迟线还是波长转换器

该文研究了光分组网络的冲突处理问题,提出了两种异于传统设计方法的交换结构．研究表明：对于非突发性业务,非简并排列方式的光纤延迟线是成本聚低的解决手段;而对于突发业务,将波长转换器和延迟线结合使用是兼顾分纽丢弃性能,系统体积和成本的较好策略．文中基于此给出了系统设计原则,该原则可确保系统节约大量的波长转换器和延迟线。对改善系统的整体性能十分有利．     

Design of All-Optical Contention Detection and Resolution for 40-Gb/s Label-Switched Routers

We present a new scheme for all-optical contention detection and time-domain contention resolution of optical packets in label-switched routers that employ all-optical label recognition. The contention detection subsystem provides all the necessary control signals required to drive an optically controlled buffer which employs 1 times 2 optical switching elements and an optical fiber delay line. The state of the buffer is dynamically controlled on a per-packet basis with all the decisions and processing performed in the optical domain. Physical layer simulations show successful buffering and forwarding of 40-Gb/s optical packets with 2-dB power penalty     

3-Dimensionally Integrated Planar Optics for 100 Gb/s Optical Packet Address Detection

We propose a novel planar optical interconnection scheme for 100 Gb/s optical packet address detection, which consists of waveguide grating couplers and a diffractive microlens integrated on a glass substrate 3-dimensionally. Length and duty cycle of the grating couplers have been determined on the bases of the ray-optic propagation-mode analysis in a slab waveguide and of the rigorous coupled-wave diffraction analysis for out-coupled radiation-modes. The 3-dimensionally integrated planar optics makes it possible to connect each address bit-signals of TE₀-waveguide mode to the detector with a power uniformity of 6.4 % and a total coupling efficiency of 72.3 %.     

Optimized Combination of Converter Pools and FDL Buffers for Contention Resolution in Optical Burst Switching

Optical burst switching (OBS) has attracted interest as a transport network architecture for the future optical Internet. As OBS relies on statistical multiplexing efficient contention resolution is a key issue in order to achieve a low burst loss probability. First, this paper discusses options and key design parameters for contention resolution in OBS. Then, it evaluates the performance of OBS nodes which employ shared wavelength converter pools and simple fiber delay line (FDL) buffers. Finally, optimized strategies for the order of probing a wavelength converter pool and an FDL buffer for contention resolution are presented and compared. It is shown that these strategies can be used to optimize performance for a given, for example, minimal cost, dimensioning of the wavelength converter pool and the FDL buffer.     

850/1550nm智能集成分波光开关的理论设计

理论分析和设计了一种用于850和1550nm两个光通信窗口的、集波长信号分离和光开关功能于一体的智能集成分波光开关，并将弧形结构全内反射面用于该集成结构中. 基于Si基半导体SiGe合金材料的等离子体色散效应，对该结构智能集成分波光开关的串音、损耗、消光比等特性进行了分析和模拟计算. 计算得到，作为光开关时器件的平均串音、插入损耗和消光比分别为-19, 1.3和21dB，作为分波器时平均串音和插入损耗分别为-11和1.1dB. 设计结果表明，该集成器件不仅能够实现850和1550nm两种波长光信号的开关，而且还能对这两种波长的光信号进行分离，是一种有前途的智能化集成分波光开关.     

850/1550nm智能集成分波光开关的理论设计

理论分析和设计了一种用于850和1550nm两个光通信窗口的、集波长信号分离和光开关功能于一体的智能集成分波光开关,并将弧形结构全内反射面用于该集成结构中.基于Si基半导体SiGe合金材料的等离子体色散效应,对该结构智能集成分波光开关的串音、损耗、消光比等特性进行了分析和模拟计算.计算得到,作为光开关时器件的平均串音、插入损耗和消光比分别为-19,1.3和21dB,作为分波器时平均串音和插入损耗分别为-11和1.1dB.设计结果表明,该集成器件不仅能够实现850和1550nm两种波长光信号的开关,而且还能对这两种波长的光信号进行分离,是一种有前途的智能化集成分波光开关.     

850/1550nm智能集成分波光开关的理论设计

理论分析和设计了一种用于850和1550nm两个光通信窗口的、集波长信号分离和光开关功能于一体的智能集成分波光开关,并将弧形结构全内反射面用于该集成结构中.基于Si基半导体SiGe合金材料的等离子体色散效应,对该结构智能集成分波光开关的串音、损耗、消光比等特性进行了分析和模拟计算.计算得到,作为光开关时器件的平均串音、插入损耗和消光比分别为-19,1.3和21dB,作为分波器时平均串音和插入损耗分别为-11和1.1dB.设计结果表明,该集成器件不仅能够实现850和1550nm两种波长光信号的开关,而且还能对这两种波长的光信号进行分离,是一种有前途的智能化集成分波光开关.     

Start-Bit Detection and Gate-Pulse Generation Using Phase-Modulated Preamble for Asynchronous Packet Processing

Start-bit detection and a single gate pulse generation scheme scalable to high-speed operation for asynchronous packet processing have been achieved. It is based on phase-modulated two-bit preamble for a coder and one-bit-delayed detection combined with a balanced photodetector as exclusive or (xor) function for a decoder. By using pi/2 phase-shifted first-bit and a pi/2 phase-shifted one-bit delay line, a single gate pulse can be generated with high speed, regardless of packet period. We have successfully achieved the single gate-pulse generation with bit rate of 10.72 Gb/s and various packet periods from 12.8 to 120 ns. Amplitude of the gate pulse was almost constant with fluctuation of plusmn5%. Suppression ratio of a gate pulse could be improved up to 9.5 dB via nonlinear absorption characteristics of an electroabsorption modulator. Autonomous gating operation for an optical digital-to-analog converter was also verified for two-bit operation     

光模块内置OTDR数据及格式分析

为了满足日益增多的PON 的网络光纤检测需求,光模块内置OTDR 技术正在不断地发展完善,提出了基于光模块内置OTDR的PON系统架构中OTDR相关接口的数据传输接口功能和数据分析功能,确定了OTDR数据文件结构,分析梳理了OTDR的数据内容,定义了OTDR的数据格式,目的是能够实现通用的内置OTDR数据格式,促进内置OTDR技术产业发展成熟。     

Broadband-Frequency-Tunable Sub-Terahertz Wave Generation Using an Optical Comb, AWGs, Optical Switches, and a Uni-Traveling Carrier Photodiode for Spectroscopic Applications

We present a monochromatic sub-terahertz signal generation technique using an optical comb signal, arrayed waveguide gratings (AWGs), and a uni-traveling carrier photodiode (UTC-PD) for spectroscopic applications. This scheme offers random or continuous frequency tuning in the range between 100 GHz and up to 1 THz. In addition, since a RF synthesizer is employed as a reference signal source of the photonic frequency multiplier, frequency locking with external instruments and reliable operation are offered. Highly coherent optical comb signal for the photonic frequency multiplication provides a narrow linewidth and very low phase noise in the generated sub-terahertz signal. For 125 GHz, the phase noise is approximately $-92$ dBc/Hz at the offset frequency of 10 kHz. This is larger than that of the 25-GHz RF source by about 13 dB and agrees well with the theory regarding phase noise multiplications due to frequency multiplication. For generating monochromatic signals, unwanted spurious signals are suppressed in the optical domain over a wide range with two AWGs, and the suppression ratio is expected to be better than 46 dBc. Utilizing the implemented sub-terahertz signal generator with a J-band UTC-PD module, absorption lines of N$_{2}$O were measured in the frequency range between 240 and 360 GHz and compared with theoretical calculations.      

EEG Data Classification for Mental State Analysis Using Wavelet Packet Transform and Gaussian Process Classifier

Stress is one of the most common problems that is faced by a majority of the students. Long-term stress can lead to serious health problems, for example, depression, heart disease, anxiety, and sleep disorder. This paper proposes an efficient stress level detection framework to detect the stress in students using Electroencephalogram (EEG) signals. The framework classifies stress into three levels; low stress, medium stress and high stress. In this experiment, EEG data is collected from six subjects by placing two electrodes in the prefrontal region. During each trial, the subject solves arithmetic questions under some time pressure. The EEG data is collected while the subject solves the question. The collected data is pre-processed using a band-pass filter to remove artefacts and appropriate features are extracted through the wavelet packet transform and PyEEG module. ReliefF feature selection method is used to select the best features for classification. The selected feature set is classified into three categories using Gaussian Classification. The proposed framework effectively classifies the level of stress with an accuracy of 94%.

     

Neural-Network-Based Sensor Fusion of Optical Emission and Mass Spectroscopy Data for Real-Time Fault Detection in Reactive Ion Etching

To achieve timely and accurate fault detection in reactive ion etching, neural networks (NNs) have been applied for the fusion of data generated by two in-situ sensors: optical emission spectroscopy (OES) and residual gas analysis (RGA). While etching is performed, OES and RGA data are simultaneously collected in real time. Several pre-determined, statistically significant wavelengths (for OES data) and atomic masses (for RGA signals) are monitored. These data are subsequently used for training NN-based time series models of process behavior. Such models, referred to herein as time series NNs (TSNNs), are realized using multilayered perceptron NNs. Results indicate that the TSNNs not only predict process parameters of interest, but also efficiently perform as sensor fusion of the in-situ sensor data.     

FDRF: Fault Detection and Recovery Framework for Seamless Data Transmission in Remote Health Monitoring Using WBAN

Wireless Personal Communications - Health monitoring systems based on Sensors, IoT and Cloud server have gained popularity in recent time. In this work patient either wear small sensors or they are...     

基于视线测量改进的主被动联合探测数据关联

针对主被动传感器异地配置情况,利用视线测量转换过程,对主被动联合探测的数据关联算法进行了改进:首先,计算视线垂足至主动传感器的距离,以方位测量与该距离之差(测量差)构造新的统计量,通过视线间距以及测量差两个统计量检验初选出候选关联集;接着,主被动视线交叉将不完整的被动测量补充为完整测量,用精度加权法实现多角度测量之间的融合,得到候选集的定位点估计,计算各定位点与目标的关联概率;然后,以视线间距和测量差构造测量距离,利用测量距离之和表征关联集内部各视线的紧密度,给出视线关联度;最后,用视线关联度修正关联概率,最大值搜索正确关联组合。仿真实验结果验证了算法的有效性。     

An Integrated Network Using Fiber Optics (INFO) for the Distribution of Video, Data and Telephony in Rural Areas

This paper reviews systems which could be suitable for providing integrated broadband and narrowband telecommunications services in rural areas, using fiber optics as the transmission medium. Systems are compared for complexity and operational features, and the principal components in each system are described briefly.     

Analytical Solution for Sparse Data Interpolation Using Geodesic Distance Affinity Space: Application to the Optical Flow Problem and 3D Reconstruction

Journal of Communications Technology and Electronics - In this paper, we derive the analytic solution for sparse data interpolation using the geodesic distance affinity space of the known reference...