Paolo Ghelfi

Optical Cross Connects Architecture with per-Node Add&Drop Functionality

We propose a cost-effective implementation of reconfigurable add&drop functionality in Optical Cross Connects based on the concept of common add&drop in the node (OXC with per- Node Add&Drop, OXC-NAD). The proposed architecture constrains usable transponders wavelengths, but the analysis on significant mesh topologies demonstrates that this does not affect the behavior of the transparent networks. The OXC-NAD is shown to also significantly reduce the node cost irrespective of the nodal degree.

All-optical digital processing through Semiconductor Optical Amplifiers: State of the art and perspectives

In order to meet the ever-increasing demand of data communication for future optical networks and optical computing, high-speed photonic digital processing is required. Elementary blocks, performing basic operations are the building elements for more complex subsystems implementing all-optical digital processing. These functions include elementary optical logic gates as well as complex photonic combinatorial networks. Semiconductor Optical Amplifiers are here considered as a possible technological choice including a review of best results, main perspectives and limitations.

Ultra-fast clock recovery by all-optical PLL

An all optical phase-locked loop (OPLL) composed by an optical voltage-controlled oscillator (OVCO), and an ultra-fast optical phase-comparator (OPC) is presented. 10 GHz pre-scaled clock extraction from a 40 GHz multiplexed signal is demonstrated.

All-electrical equivalent model for mode locked fiber sources synchronization schemes based on electro-optical PLLs

Nowadays the quick increase of the band demand in the optical transmission systems, leads to study all-optical techniques of signal processing to overcome the limits of the electro-optic devices. The optical time division multiplexing (OTDM) technique represents an effective possibility to reach transmission rates per channel higher than 160 Gbit/s. The analysis of the all-optical signal processing blocks which make up the OTDM system becomes very complex because it has to take into account all the linear and non-linear optical effects. An equivalent simple all-electrical model is desirable for a proper design of high performances all-optical schemes. In particular in this work we consider a PLL (phase locked loop) synchronization system between a regenerative ML (mode locked) fiber source and an external clock signal.

Effective Sample Parallelization in a Single Nonlinear Device for High Sampling Rate Photonic Assisted ADC

An effective parallelization scheme in a single nonlinear device for high-sampling-rate photonic-assisted ADC is presented. 10-fold parallelization of 9.95GS/s signal is experimentally demonstrated with capability for 6-bits ENOB. Potentials for larger parallelization is also discussed.

Power optimization for intensity and time jitter characterization in optical frequency multiplication and time multiplexing

Intensity and time jitter characterization in optical frequency multiplication and time multiplexing is theoretically described. The power constraints are experimentally measured for a 10 to 20 GHz optical frequency multiplication system.

Design of Reliable Metro Core Networks

In this study the design of reliable network topologies is applied to a typical metro network scenario. Results show that, with an increasing amount of traffic, ring topologies represent a less attractive solution and, on the other hand, highly connected DWDM mesh networks are required to grant the required level of throughput for bandwidth demanding applications and services.

All-Optical Packet Routing based on Integrable 2×2 Switch for Data Packets up to 160 Gbit/s

An all-optical, integrable, ultra-fast 2times2 spatial switch based on cross-gain-modulation in semiconductor optical amplifiers able to process signals up to 160 Gbit/s is demonstrated. Penalty measurements confirm the effectiveness of the proposed scheme in cascade configurations.

Experimental validation of an extended ABCD model for actively mode-locked fiber lasers

An extended ABCD model for actively mode-locked fiber lasers is presented. This new scheme includes the amplifier model taking into account the power evolution along the cavity fiber. The first experimental validation is reported.