Guiling Wu

Stable dynamic detection scheme for magnetostrictive fiber-optic interferometric sensors

A stable dynamic detection scheme for magnetostrictive fiber-optic interferometric sensors is studied. The working principle is presented and the experimental verification is performed. The results show that the system employing the dynamic detection scheme has better stability and sensitivity in comparison with the system employing quadrature control technique.

18 wavelengths 83.9Gs/s optical sampling clock for photonic A/D converters

In this paper, a simple approach to generate the time-wavelength interleaved sampling clock for photonic A/D converters is proposed using commercially available mode-locked femtosecond fiber laser and optical wavelength/time division multiplexing (WDM/OTDM) techniques with low cost passive optical components. A time and wavelength mapping module is configured using specially designed wavelength division multiplexer and mechanical tunable fiber stretchers. OTDM modules with low optical insertion loss and flexibly configurable multiple factor are implemented with the fused-biconical optical fiber couplers. Experiment is carried out using 18 WDM channels and 128 times OTDM to demonstrate the generation of 83.9Gs/s time-wavelength interleaved sampling clock.

Multi-objective optimization based on ant colony optimization in grid over optical burst switching networks

A multi-objective task scheduling approach for grid over optical burst switching (GOBS) networks is proposed. It takes into account the selection of both computational resource and network resource and is able to simultaneously satisfy three objectives representing the requirements of grid users and resource providers, namely completion time, payment and load balancing. An ant colony optimization algorithm (ACO) for this multi-objective GOBS optimization problem is designed. The convergence and diversity preserving of the algorithm is compared with the nondominated sorting genetic algorithm (NSGA-II) through three performance metrics. Simulations are carried out to compare grid and network performance of these two algorithms. Grid scheduling performance comparison between single-objective optimization and multi-objective optimization based on ACO is also taken by simulations.

Robust, compact, and flexible neural model for a fiber Raman amplifier

In this paper, a novel robust, compact, and flexible neural-network model for a fiber Raman amplifier (FRA) is presented. The model can be used in various applications with promising accuracy and low requirement for memory. Analytical expressions are derived in order to make the optimal pump-power configuration much easier, and the computational time is reduced dramatically in comparison with other gain-design methods in real-time pump-power adjustment. The calculated on-off gain spectrum and the noise figure using the proposed model agree well with the experimental results. The model has a potential value in simulation and pump-power dynamic control.

A Photonic RF Phase Shifter Based on a Dual-Parallel Mach–Zehnder Modulator and an Optical Filter

A photonic RF phase shifter using a dual parallel Mach–Zehnder modulator (DPMZM) and a tunable optical band-pass filter is demonstrated. The dependences of the linearity and power stability of the proposed RF phase shifter on the performance of the DPMZM and the optical filter are theoretically analyzed and numerically simulated. In the experiment, a continuously tunable range of more than 450° phase shift and a small power variation of less than 1.6 dB for a wideband RF range (8–12 GHz) are achieved by simply tuning the bias voltage of the DPMZM. The experimental results agree well with the theoretical analysis.

Exact analytical solution for Raman fiber laser

In this letter, Raman fiber laser (RFL) is studied theoretically with experimental demonstration. With the assistance of the Lambert function, the coupled equations describing the optical power evolution in the RFLs are solved analytically. The procedures to get the analytical solution are described in detail. The results are verified by the numerical simulations and the experimental demonstrations.

A novel algorithm for a multi-cavity Raman fiber laser

In this paper a Raman Fiber Lasers (RFLs) with several embedded cavities are studied. A novel algorithm is proposed to solve the coupled equations describing the optical power evolution in a RFL. By using some invariant constants as the boundary condition at the output end, the problem of solving ordinary differential equations (ODEs) with guessing boundary value is translated into a two-boundary-condition ODE problem. The algorithm is based on Newton-Raphson method and proved rather fast and stable. Quantitative analysis is performed based on the algorithm.

An Index-Based Parallel Scheduler for Optical Burst Switching Networks

In this paper, an index-based parallel scheduler for optical burst switching (OBS) networks, which can find feasible voids on different channels in parallel with O(1) time complexity, achieve the highest possible efficiency, and is suitable for efficient hardware implementation, is proposed. The channel scheduler proposed consists of two phases: searching the feasible voids on all data channels and selecting optimal void among feasible voids found. In the first phase, an index vector of voids for each channel is constructed by dividing the scheduling time window of the channel into N slots, and an index-based searching approach is applied in parallel to each channel to find the feasible voids by a few simple index based bit operations and once memory reading and comparing operations. A configurable optimal void selection approach, which selects optimal void according to the external configurable signal by using a configurable comparand translator and a general selection process, is designed to supported different scheduling algorithms such as LAUC-VF, Min-SV, Max-EV, and Best-Fit with full efficiency. Formulae for important design parameters are given. The hardware architecture of the index based parallel scheduler is designed, and a 16-channel scheduler with the full resource utilization of LAUC-VF is implemented in FPGA (Field Programmable Gate Array) with a scheduling time of 33.3 ns per burst request. The support to different scheduling algorithms is also validated experimentally.

Digitally tunable optical filter based on DWDM thin film filters and semiconductor optical amplifiers

We demonstrate a novel digitally tunable optical filter, which is based on dense wavelength division multiplexed (DWDM) thin film filters and semiconductor optical amplifiers (SOA). It has the advantages of fast tuning speed, large tuning range, good temperature stability, simple control mechanism. It is also scalable without bringing additional insertion loss. The passband wavelengths are in consistency with those suggested by ITUT.

High-Precision Time Transfer Over 2000-km Fiber Link

Manuscript received September 28, 2015; revised October 26, 2015; accepted November 5, 2015. Date of publication November 10, 2015; date of current version November 20, 2015. This work was supported in part by the National Natural Science Foundation of China under Grant 61127016 and Grant 61107041 and in part by Specialized Research Fund for the Doctoral Program of Higher Education of Ministry of Education under Grant 20130073130005.