A SIMPLE AND CONVENIENT ROUTE FOR PREPARATION OF OPTICALLY ACTIVE BICYCLOLACTONES

Optically active bicyclolactones 4 were prepared via a new simple route.

Study on the performance of the A*Prune QoS routing algorithm for intelligent optical networks and its improvements

The A＇Prune quality of service （QoS） routing algorithm was proposed to compute K-shortest paths satisfying multiple QoS constraints, The A＇Prune is considered to be one of the practical routing algorithms for intelligent optical networks because of its flexibility in handling many practical constraints, This article gives detailed performance studies of the algorithm through extensive simulation experiments. We found that both the running time and the memory space requirements of the algorithm are large, especially when the network size increases, in this article, we also propose an approach to improving the performance of the A＇Prune algorithm. The improvements should make the A＇Prune algorithm more attractive for practical use in intelligent optical networks.

Orbital-angular-momentum-based reconfigurable optical switching and routing

Orbital angular momentum(OAM) has gained interest due to its potential to increase capacity in optical communication systems as well as an additional domain for reconfigurable networks. This is due to the following:(i) coaxially propagated OAM beams with different charges are mutually orthogonal,(ii) OAM beams can be efficiently multiplexed and demultiplexed, and(iii) OAM charges can be efficiently manipulated. Therefore, multiple data-carrying OAM beams could have the potential capability for reconfigurable optical switching and routing. In this paper, we discuss work involving reconfigurable OAM-based optical add/drop multiplexing, space switching,polarization switching, channel hopping, and multicasting.

Optical Packet Routing Performance of an Optical Packet Switch With an Optical Digital/Analog-Conversion-Type Header Processor (Wavelength Label Switch)

We demonstrate the routing operation of optical packets by an optical packet switch consisting of an optical digital-to-analog conversion-type header processor, a wavelength converter using an electrically-tunable laser, and an arrayed-waveguide grating router. A packet transfer by two-bit optical header was achieved for the first time.

Multi-Wavelength Optical Packet Routing Technologies Based on Superstructured Fiber Bragg Gratings

A WDM compatible Edge-to-Edge Self-Routed optical packet switched network that simplifies the optical processing is proposed. The system employs all-optical packet label generation and recognition using coded superstructured Fiber Bragg gratings.

Research of novel complex optical network routing architecture

This article puts forward a novel routing architecture for complex optical network,which core component is path calculation element （PCE）.As is well known,the PCE-based distributed path computation structure is making the routing control and computation loosely coupled from traditional control plane.In the study,the resource allocation and routing algorithm are the critical part of PCE hierarchy.To compare the performance of new architecture and the traditional one,the user uses the flooding suppression,routing delay,resource utilization and traffic blocking probability as performance simulation parameters and taking the verification simulation on objective modular network testbed （OMNeT） platform against to source-node routing architecture.The numerical analysis,computer simulation and experiment work indicate that the operation of PCE-based routing architecture can reduce the flooding information of path calculation request as well as the routing hops significantly and improve the quality of service （QoS） by decreasing the blocking probability when failure happened.

Silicon non-blocking 4×4 optical switch with automated polarization adjustment

We demonstrate a polarization-insensitive silicon 4×4 optical switch based on Mach–Zehnder interferometer(MZI)switch elements.On-chip polarization controllers are integrated before the switch fabric to automatically adjust an arbitrary input polarization to the transverse electric mode.The 4×4 switch fabric is based on a dilated double-layer network architecture to completely cancel the first-order crosstalk.Thermo-optic phase shifters are integrated in the MZI switch elements and the polarization controllers for adjustment of the switching state and polarization,respectively.We develop a polarization control algorithm based on a gradient descent method for automated polarization control.The polarization recovery time is less than 4 ms,and the measured polarization-dependent loss is~2 d B.The scheme provides a new solution for realizing polarization-insensitive silicon optical switches.