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This paper investigates experimentally the suitability of low-cost vertical cavity surface emitting lasers (VCSEL) for radio-over-fibre transmission of UMTS signals. Three directly-modulated VCSEL configurations are investigated: Multi-mode VCSELs operating at 850 nm and 1300 nm respectively in multi-mode fibres (MMF), and single-mode VCSELs operating at 1310 nm with standard single-mode fibre (SSMF)...
Optical technology allows to design an inter-satellite network able to guarantee the data transfer between different places on Earth, at high data rate. Proposed optical network is composed by 27 Medium Earth Orbit (MEO) satellites as network nodes, distributed over three different orbits; communication is established at an access node and reaches the destination node through a number of hops on intra-orbit...
In this paper electromagnetic properties of periodic arrays of single-wall metallic carbon nanotubes (CNs) are presented. Semiclassical model, based on periodic Green's function, which takes into account electromagnetic interaction between nanotubes, is developed. Quantum properties of nanotubes are taken into account via the complex conductance. Propagating and evanescent eigenwaves in infinitely...
This paper focuses on survivable optical networks and studies in detail the network performance improvement that can be achieved when jointly considering network resilience and physical layer constraints. The protection scheme used is path-based shared protection known as backup multiplexing. In the proposed solution routing and wavelength assignment for both primary and protection paths are jointly...
We describe the comparative analysis of the power consumption between optical cross-connect equipment based on electrical and photonic matrix switching, which will be used for future large capacity optical networks. For optical networks that accommodate several Tb/s-class capacity traffic, the power consumption of optical cross-connect equipment based on electrical switching could reach more than...
Optical networks are fairly static and operate within well-defined specifications. The addition of new nodes or the upgrade of existing links demands an enormous expenditure. A cost-effective implementation of future optical networks should accommodate old static networks, as well as new highly-efficient networks. It also should be intelligent, self-managed, monitored and dynamically-reconfigurable...
We discuss the role of physical fluctuations in physical random bit generators focusing on the practical limits of generation rates. First we present a brief review of existing random bit generators, their mechanisms and performance characteristics. Then we discuss in detail random bit generation by chaotic lasers. It has recently been shown that bit sequences which passed statistical tests of randomness...
Transparent networks promise a cost efficient solution for future core and metro networks, due to the high efficiency for switching trunk traffic. Network availability is an important performance parameter for network operators, who are incorporating protection and restoration mechanisms in the network to achieve competitive advantages. This talk will focus on the CAPEX reductions expected from implementing...
PlaNet is a multilayer network planning tool designed and developed at the University of Texas at Dallas. This paper illustrates some of the features of PlaNet-OTN, one of the modules available in the PlaNet tool. PlaNet-OTN can be used to design and plan an optical transport network (OTN), which is comprised of two layers: wavelength division multiplexing (WDM) layer, which deals with wavelength...
This article addresses the dynamic provisioning of optical connections within a GMPLS-enabled translucent wavelength switched optical network with sparse 3R regenerators. To this end, an OSNR-based IRWA algorithm computes routes that aim at satisfying both restrictions: the wavelength continuity constraint and adequate end-to-end optical signal quality. If either constraint cannot be satisfied, the...
We propose a novel online physical-layer impairment-aware routing algorithm taking into account a minimum quality of transmission (QoT) constraint, which must be satisfied in all cases, even if the network load is changing, and new channels are activated. Our online constraint-based routing (CBR) algorithm considers the actual network load to get a more exact prediction of the signal quality degradation...
Many simulative approaches have been proposed to investigate semiconductor optical amplifier (SOA) behaviour, in order to model its performance when used in several scenarios. Most of the applications of SOAs are based on the propagation of maximum two signals within the active medium, thus, higher order phenomena due to beating of more than two signals are not always correctly predicted by usual...
We propose a bidirectional reflective semiconductor optical amplifier (RSOA) based wavelength-division-multiplexing passive optical network (WDM-PON) utilizing a differential phase shift keying (DPSK) signal for down-link and an on-off keying (OOK) signal re-modulated for up-link with high extinction-ratio in both directions. A 20 km range colorless WDM-PON without dispersion compensation was demonstrated...
We fabricated and characterized a vertical-cavity surface-emitting laser (VCSEL) based on (110) InGaAs/GaAs multiple quantum wells (MQWs). Circularly polarized lasing in the (110) VCSEL by optical injection of spin-polarized electrons has been demonstrated at 77 K and room temperature. A high degree of circular polarization, 0.94, was observed at 77 K, reflecting the long electron spin relaxation...
An interferometric setup for measuring Polarization Mode Dispersion (PMD) setup was tested. Using a low-coherence technique with a Michelson interferometer, it was possible to measure values of PMD from detected Differential Group Delay (DGD) values in two reels. The low-coherence source bounds the minimum value of DGD detected to 0.13 ps, leading to a minimum value detected around 0.14 ps. The mean...
Present-day data networks are being challenged by the relentless growth of bandwidth demand. Most of this future growth, however, is not arising from more users with the same application bandwidth demands, but rather from the dramatic increase in bandwidth demand of emerging applications. The compounding of these two trends has set the stage for optical networking technology to make significant contributions...
We experimentally study the characteristics of optical rogue waves in supercontinuum generation in the femtosecond regime. Specifically, the intensity histograms obtained from spectrally filtering the supercontinuum exhibit the L-shaped characteristics typical of extreme-value phenomena on the long wavelength. Furthermore, the form of the histogram on the long wavelength edge varies from L-shaped...
Several alternatives have been investigated to achieve enhanced supercontinuum generation in the nanosecond pump regime using specialty silica-based microstructured optical fibers (MOFs). Among these alternatives we can point out the use of (a) MOF tapers, (b) highly Ge-doped core Y-shaped MOF and (c) Er-doped MOF. These specialty MOFs provide either an increased material nonlinear response or a rather...
This paper reviews recent progress in the fabrication of soft glass microstructured optical fibres with nanowire core sizes, with nanoscale holes in the fibre core itself and with large mode areas. We demonstrate the potential of these fibres for a wide range of applications including high optical nonlinearity, bio/chemical sensing, high-resolution imaging and nano-lithography, mid-infrared high power...
In the past few years optical networks experienced, as a long wave effect, a substantial increase in the transported bandwidth in all the sectors. From the high speed transport to the low speed access up to the end user. At the event horizon, the introduction of mixed fully transparent networks, ring+tree, to cover all the metro-access scenario, open the way to the implementation of extended metro...
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