智能变电站监控信息验收过程涉及到变电站与调控主站的多个环节.基于现有技术体系创新提出了面向调控业务满足全回路验收要求的变电站监控信息自动验收解决方案,对常规验收与自动验收进行了优势分析.设计了自动验收系统架构,面向新建变电站与改扩建变电站两种应用场景,给出了不同的实施方案.重点分析了变电站侧自动验收实现技术,提出了基于定制策略的信息源触发技术,实现主子站交互信息的一键触发.基于模块化思想研制了自动验收装置,并进行了实验验证及实际工程应用.经实践验证智能变电站监控信息自动验收技术极大地提高了验收效率,突破了主子站交互信息自动验收的技术瓶颈,具备全面推广应用的条件.

在风暴灾害影响下,传统的故障远程监控方法存在监控时间过长、误差率较高等问题.针对以上不足,提出一种基于Petri网的风暴灾害下的输电线路运行故障远程监控技术.融合输电线路的电气量及开关量数据,根据融合结果,运用故障模式匹配与Petri网技术提取故障特征;由故障特征构建网络拓扑结构矩阵,把故障方向传给主机,根据主机上输电线路各点的故障方向构建故障信息矩阵,对两个矩阵进行运算来远程监控输电线路运行故障.分析实验数据可知,运用该远程监控技术对风暴灾害下输电线路运行故障进行监控时,监控时延保持在22～ 27 ms之间,监控误差率基本保持在20％以下,远低于传统技术.

We report an optical frequency comb (OFC) generation by using a single dual-drive Mach-Zehnder modulator (DD-MZM). Over 21 comb modes with optical power above -5 dBm and power flatness of 0.81 were generated within the -6 dB bandwidth of the OFC optical spectrum. 10 Gb/s OOK data modulation were applied to the optical combs, and error free transmission were achieved after 10-km SSMF. The results indicated that a total capacity of 210-Gb/s WDM optical interconnection link can be enabled by the OFC based on a single DD-MZM with potentially 44% reduction of power consumption compared the case of using multiple laser diodes.

We reported 40-Gb/s PAM4 transmission over 10-km SSMF with 2-dB penalty and 6-dBm sensitivity at BER of 2E-4, using directly modulated $1.5-\mu\mathrm{m}$ VCSEL, with the bandwidth enhancement from 6.4-GHz to 9.35-GHz by offset optical filtering.

Discrete Multitone Transmission (DMT) transmission over standard multimode fiber (MMF) using high-speed single (SM) and multimode (MM) Vertical-Cavity Surface-Emitting Lasers (VCSELs) is studied. Transmission speed in the range of 72Gbps to 82Gbps over 300m - 100m distances of OM4 fiber is realized, respectively, at Bit-Error-Ratio (BER) <5e-3 and the received optical power of only -5dBm. Such BER condition requires only 7% overhead for the conversion to error-free operation using single Bose-Chaudhuri-Hocquenghem forward error correction (BCH-FEC) coding and decoding. SM VCSEL is demonstrated to provide a much higher data transmission capacity over MMF. For 100m MMF transmission SM VCSEL allows 82Gbps as compared to MM VCSEL resulting in only 34Gbps at the same power (-5dBm). Furthermore, MM VCSEL link at 0dBm is still restricted at 100m distance by 63Gbps while SM VCSEL can exceed 100Gbps at such power levels. We believe that with further improvement in SM VCSELs and fiber coupling > 100Gbps data transmission over > 300m MMF distances at the BER levels matching the industry standards will become possible.

We reported 40-Gb/s PAM4 transmission over 10-km SSMF with 2-dB penalty and 6-dBm sensitivity at BER of 2E-4, using directly modulated 1.5-μm VCSEL, with the bandwidth enhancement from 6.4-GHz to 9.35-GHz by offset optical filtering.

Single-lane 120Gbps-BtB, 118Gbps-100m, 117Gbps-200m and 112Gbps-300m discrete multi-tone transmission based on a single-transverse-mode 850nm band VCSEL is investigated respectively over standard OM4 multimode fiber. This proves our previous conclusion of single-lane capacity beyond 100G by more optical coupling power.

82Gbps (over 100m), 75Gbps (200m), and 72Gbps (300m) transmission is achieved at BER <5e-3 using single mode VCSEL and DMT modulation with received optical power of -5 dBm. 100Gbps is evaluated by reducing coupling loss.

By employing an injection locked FP laser (IFP), we successfully achieved 56 Gbps PAM-4 transmission over 2 km SSMF. The IFP laser behaves as a colorless CW source, and 32 DWDM wavelengths are generated by simply connecting the FP laser to different DWDM multiplexer port. These results indicate a beyond Tbps 2km connection solution by densely wavelength multiplexing the IFP transmitter.

We review an optical flat datacenter network (DCN) based on scalable optical switching system with port-count independent low latency. Generation/reconfiguration of virtual DCN by utilizing statistical multiplexing offered by the optical switching system is demonstrated.

Photonic integration of optical packet switching modules is crucial to compete with existing electronic switching fabrics in large data center networks. The approach of coding the forwarding packet information in an in-band label enables a spectral-efficient and scalable way of building low-latency large port count modular optical packet switching architecture. We demonstrate the error-free operation of the four in-band label extraction from 160 Gb/s optical data packets based on photonic integrated silicon-on-insulator ring resonators. Four low-loss cascaded ring resonators using the quasi-TM mode are used as narrowband filters to ensure the detection of four optical labels as well as the error-free forwarding of the payload at limited power penalty. Due to the low-loss and less-confined optical quasi-TM mode the resonators can be very narrowband and have low insertion loss. The effect of the bandwidth of the four ring resonators on the quality of the payload is investigated. We show that using four rings with 3dB bandwidth of 21 pm and only an insertion loss of 3 dB, the distortion on the payload is limited (<;1.5 dB power penalty), even when the resonances are placed very close to the packet's central wavelength. We also investigate the optical power requirements for error-free detection of the label as function of their spectral position relative to the center of the payload. The successful in-band positioning of the labels makes this component very scalable in amount of labels.

We propose and demonstrate an optical flat data center network based on scalable optical switch system with optical flow control. Experimental evaluation of the system at data rate of 40 Gb/s includes a 4×4 optical switch with highly distributed control for port-count independent nanosecond reconfiguration time for low latency operation. The hardware flow control at the optical level allows fast retransmission control of the electrical buffered packets at the edge nodes preventing the need of optical buffers. Moreover, this makes a dedicated flow control network redundant, which effectively reduces system complexity and power consumption. Dynamic switch operation reported 300 ns minimum end-to-end latency (including 25 m transmission link) and <; 10-6 packet loss for 0.4 load with buffer size of 16 packets.

A type of tunable femtosecond soliton logic gate based on fiber Raman Self-Frequency Shift (SFS) is studied in this paper. The Raman SFSs of femtosecond solitons governed by the Newton's cradle mechanism in logic gate are analyzed with an Improved Split-Step Fast Fourier Transform (ISSFFT) algorithm. The impact factors of the solitonic pulse frequency shift and temporal time shift, which are included the Third-Order Dispersion (TOD) effect, are investigated. The existing theoretical equation of SFS is modified into a new expression for this type of soliton logic gate. A lower switching power and the small size of the soliton logic gate device is designed to realize the logic functions of AND, NOT, and XOR. The results demonstrate that the logic gate based on SFS is belonged to the asynchronous system and can be achieved with Milli-Watt switching power and good extinction ratio. ISSFFT is effective and accurately to analyze higher-order dispersive and nonlinear effects in the logic gates.

We propose and demonstrate an optical flat datacenter network based on scalable optical switch system with optical flow control.Modular structure with distributed control results in port-count independent optical switch reconfiguration time.RF tone in-band labeling technique allowing parallel processing of the label bits ensures the low latency operation regardless of the switch port-count.Hardware flow control is conducted at optical level by re-using the label wavelength without occupying extra bandwidth, space, and network resources which further improves the performance of latency within a simple structure.Dynamic switching including multicasting operation is validated for a 4x4 system.Error free operation of 40 Gb/s data packets has been achieved with only 1 dB penalty.The system could handle an input load up to 0.5 providing a packet loss lower that 10 -5 and an average latency less that 500ns when a buffer size of 16 packets is employed.Investigation on scalability also indicates that the proposed system could potentially scale up to large port count with limited power penalty.

Bandwidth-hungry internet services like cloud computing, social networking and video sharing generate large volumes of packetized traffic within data centers (DCs). Inter-cluster communication bottleneck of current DCs tree topology causes fragmented pools of servers and high latency by employing a large port count (100s) optical packet switch (OPS) to flatten the DC network topology. However, the reconfiguration time of several OPS architectures with centralized control is port count dependent. Scaling the port count causes larger latency, and thus larger buffers for storing the packets in a flow controlled operation. We present numerical and experimental results that validate the operation of a flow-controlled optical packet switch cross-connect with distributed control and nanosecond packet switching/retransmission. Real-time operation of a random packet traffic generator with variable load, FIFO queue packet storing with buffer managers for packet retransmission, contention resolution and fast switch reconfiguration control have been implemented by using an FPGA.

In this study, we provide an experimental assessment of a quantum dash Fabry-Perot mode-locked laser for all-optical clock recovery using data streams at 40, 80, 160, and 320 Gb/s. The data streams at 80, 160, and 320 Gb/s are phase coherent signals featuring no spectral component at 40 GHz. The 40 GHz recovered optical clock signal is characterized in terms of phase noise, timing jitter, dynamic power range, and wavelength dependence for the different data rates. Our experiments demonstrate a recovered optical clock signal from a 320 Gb/s data stream with a timing jitter of 94 fs and wavelength detuned by 23 nm. In addition, the performance of the optical time division multiplexing receiver at 80 and 160 Gb/s data signals employing the recovered clock as a demultiplexing control signal and as a clock for the bit-error-rate tester (BERT) is evaluated by bit error rate measurements on the demultiplexed data signals.

We demonstrate a full functional 1×N optical packet switch employing a Silicon-on-Insulator integrated label extractor combined with a FPGA-based controller. Experimental results show error-free on-the-fly parallel and asynchronous optical label detection, processing and packet switching.

We demonstrate a compact 40Gb/s 32-channel packet demultiplexer and in-band label extractor based on photonic integrated AWG followed by a narrow-band microring resonator at each AWG output. Error free operation with ≤0.5dB penalty was measured.

Applications running inside data centers are enabled through the cooperation of thousands of servers arranged in racks and interconnected together through the data center network. Current DCN architectures based on electronic devices are neither scalable to face the massive growth of DCs, nor flexible enough to efficiently and cost-effectively support highly dynamic application traffic profiles. The FP7 European Project LIGHTNESS foresees extending the capabilities of today's electrical DCNs throPugh the introduction of optical packet switching and optical circuit switching paradigms, realizing together an advanced and highly scalable DCN architecture for ultra-high-bandwidth and low-latency server-to-server interconnection. This article reviews the current DC and high-performance computing (HPC) outlooks, followed by an analysis of the main requirements for future DCs and HPC platforms. As the key contribution of the article, the LIGHTNESS DCN solution is presented, deeply elaborating on the envisioned DCN data plane technologies, as well as on the unified SDN-enabled control plane architectural solution that will empower OPS and OCS transmission technologies with superior flexibility, manageability, and customizability.

In this work, we present the quantum dash mode-locked laser diode (QDash-MLLD) based optical clock recovery (OCR) operation from a high speed return-to-zero on-off keying (RZ-OOK) lacking in the free-running frequency components, in our case at 40 GHz.