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The distribution and use of network resources should be evaluated in order to reduce the computational and financial costs incurred in the deployment and maintenance of the network. This work presents a methodology for cost-benefit evaluation of different regenerator placement and allocation techniques for elastic optical networks. The proposed methodology is applied in scenarios with dynamic traffic...
Realistic reference networks are critical for all techno-economic evaluations in the design of an optical network architecture. As this information was not publicly available for Ireland, we generated such a reference network. In this paper we elaborate on the challenges faced during the generation and present some statistics. We also show how this is used in the design of an optical architecture...
We developed a techno-economic network planning tool for deployment of PON networks in large cities involving hundreds of thousands of end-users. The tool use techno-economic data and street-aware algorithms to estimate the global cost of the network. In the present new work, we extend the application scenario of our planning tool to estimate the increase of cost when different types of protection...
We have experimentally investigated the RF linewidth and timing jitter in self-mode-locked two-section quantum dash lasers emitting at ∼1.55 µm and operating at ∼21 GHz repetition rate, subjected to single and dual loop optical feedback into the gain section, over a wide range of feedback delay. Various feedback conditions are investigated and optimum levels determined for narrowest linewidth and...
The continued increase in Internet traffic, particularly in metro networks, is spurring wide deployment of optical networking technologies for wavelength routing. In metro networks, the number of nodes traversed can be very large and hence the optical filtering penalty incurred in the ROADM/OXC nodes can be critical as it degrades fiber frequency utilization. This presentation elucidates how grouped...
We extend past work presented at ICTON 2015, where we reviewed and extended a number of dynamic traffic grooming algorithms proposed by Zhang et al. for elastic optical networks. In that paper we showed that, on the one hand, different grooming policies lead to different connection blocking ratios and have different associated economic costs. On the other hand, different types of transceivers (supporting...
The research aims in estimating the impact of various levels of administratively imposed structural regularities and equipment uniformities on FTTH network designs. We enhance our FTTH network optimization platform with algorithms that allow imposing additional constraints on the returned solutions. We use the platform to compare, in terms of CAPEX, obtained FTTH network designs. Additionally, we...
Centralized Radio Access Network (C-RAN) is a promising mobile network architecture to face the increasing mobile traffic demand. In this paper, we propose a detailed model to evaluate the statistical multiplexing gain achieved through C-RAN baseband pooling, and based on this model we can perform a cost analysis taking into consideration different geographical type areas (geotypes). We show the influence...
Based on analogy between quantum mechanics and the classical electrodynamics, we sorted dielectric microspheres with almost identical positions of their whispering gallery mode (WGM) resonances as photonic atoms. Such microspheres were assembled in a wide range of structures including linear chains and planar photonic molecules. We studied WGM hybridization effects in such structures using side coupling...
The Abstraction and Control of Traffic Engineered Networks (ACTN) defines the requirements, use cases, and an SDN-based architecture, relying on the concepts of network and service abstraction, detaching the network and service control from the underlying data plane. The architecture encompasses Physical Network Controllers (PNCs), responsible for specific technology and administrative domains, orchestrated...
The fabrication properties of ternary and quaternary GeS2-based chalcogenide glasses are discussed in view of the removal impurities and control of crystallization by controlling the starting composition, raw materials purification and fabrication steps. The two specific compositions discussed for glass and fibre fabrication are: GeS2-Ga2S3-CsI and GeS2-Ga2S3-CsI-SnS which were optimised for multimode...
In the paper heavy metal oxide glass co-doped with Er3+/Yb3+, Ho3+/Yb3+ and triply-doped with Er3+/Ho3+/Yb3+ ions have been presented. Glass from Bi2O3 - GeO2 - Ga2O3 - Na2O system has been characterized in terms of thermal and spectroscopic properties. As a result of energy transfer between lanthanides ions and superposition of emission bands (Er3+: 4I11/2 → 4I13/2, Ho3+: 5I6 → 5I7), broadband luminescence...
We present an analysis of the spectral characteristics of distributed-feedback (DFB) laser resonators with thermally chirped distributed mirrors. Such DFB resonators have the interesting capability of producing a linewidth as narrow as a few kHz. The investigated devices are ytterbium-doped amorphous Al2O3 channel waveguides with a periodic Bragg grating inscribed into its SiO2 top cladding. The resonance...
This paper estimates the nonlinear refractive index of low attenuation bend insensitive fiber through experiments and simulation. We have studied and analysed the impact of all optical parameters such as wavelength difference of dual-frequency input signal, fiber length, effective area and dispersion on nonlinearity measurements of this fiber. In addition, a comparative study has been made between...
A new asymmetric directional coupler based on microstructured air-silica cane that achieves high coupling efficiency between a single mode fiber (SMF) and a few mode fiber (FMF) is proposed. Parallel to the propagation axis, the two fibers are inserted on either side of the central hole in a microstructured cane consisting of several rings of air holes. The structure is reduced with a reduction coefficient...
We have proposed an exhaustive experimental study of dissipative soliton resonance in a double clad Er:Yb co-doped dual amplifier passively mode-locked figure-of-eight fiber laser. By adjusting the pumping powers of the amplifiers, both the amplitude and width of the output square-wave pulse can be tuned continuously. Moreover, some other key parameters such as the net cavity dispersion and the coupling...
Far-field super-resolution (SR) microscopy has developed to be an important tool in life sciences. However, it relies on, and therefore is limited by the ability to control the fluorescence of label molecules or nanoparticles. While in many cases, label-free far-field microscopy is required, an equivalent SR technique is not available.
We demonstrate an active random fiber laser by directly pumping a 100 m erbium-doped fiber at 980 nm wavelength, with a fiber loop mirror forming a half-open cavity. Random lasing with competing spectral modes in the range from 1535 nm to 1560 nm is achieved, with the maximum lasing slope efficiency around 10%. We also study the effect of combining a dispersion compensated fiber with the erbium-doped...
The radiation pattern of a single nano-object completely encodes its multipole decomposition in amplitude, polarization, and phase. In this sense you could argue that a complete measurement of far-field information allows full resolution of the physics of a nano-object, even though converting a multipole decomposition to a near-field will require additional information on an objects size and shape...
We demonstrate the conversion of cylindrically polarized laser beams in an orthogonal polarization state by introducing a high-order vortex phase singularity. Our theoretical and experimental investigations show that increasing the order of the phase singularity leads to effective generation of azimuthal polarization from radial polarization. These results demonstrate tight interrelation of the specific...
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