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This paper discusses the path of telecom market development in Armenia since its wider opening to private participation in 1998 and the recent fast development in the sector due to elimination of monopoly in providing main telecom services. Investigation covers Internet and mobile markets and draws comparatives with other countries of the region, covering telecom market development (penetration) indicators...
This paper presents the bringing of optical fibre to domestic users in the Republic of Slovenia. Slovenia has two main Fibre-to-the-Home (FTTH) providers, deploying access network infrastructure based on Point to Point (P2P) fibre links. In recent years, accelerated deployment of the optical access network and the consequent increase in the number of optical household connections has been noted. These...
Access infrastructure combining fiber optic and wireless technologies can provide the necessary broadband access required by convergence of wireless and wired networks. Optical millimetter-wave generation using up-conversion is considered as a cost-effective solution in radio over fiber systems. In this paper we discuss and compare the robustness against dispersion of three millimetter-wave generation...
In this paper we discuss filtering schemes for performing wavelength conversion with QD-SOA. We identify that the selection of the optimum filter depends on the operating regimes of the nonlinear device. Experimental implementations of the proposed schemes demonstrate efficient wavelength conversion with high quality factors.
In this study, second harmonic generation (SHG) is studied in AlGaAs microring resonators. Efficiency of frequency conversion is investigated in single and double microring structures. The effects of input power and loss of the ring waveguide are considered. In a double microring structure, we have to take into account the effect of the generated second harmonic field, which is coupled into the next...
Microring resonator filters which are made of dielectric-loaded surface plasmon polariton waveguides and operate in the telecommunication range are thoroughly analyzed by means of 3D-FEM simulations. The filters' functional characteristics, such as the resonant frequencies, the free spectral range, the transmission bandwidth and the extinction ratio, are investigated for different values of the key...
This invited talk presents the evolution of the planar waveguide dispersive devices developed in our laboratory for spatial heterodyne spectroscopy. The basic concepts are introduced and then applied to a Mach-Zehnder interferometer array capable of a resolution of 0.1 nm over a bandwidth of 2.5 nm.
Astronomical interferometry is an active area of research and an increasing number of new conceptual ideas and designs are being proposed to achieve optimum astronomical instruments. In particular, integrated optics has a lot to offer in what concerns beam combination and control. In this paper, different examples of application of hybrid sol-gel integrated optics devices for fabrication of beam combiners...
We have shown that the Lu3-x-yBixPryFe5-zAlzO12 grown on (111) oriented GGG (gadolinium gallium garnet) substrates by the liquid phase epitaxy may be used for effective suppression of the RF magnetron radiation in the spectral range 5 - 12 GHz.
A new method based on the well-studied boundary element method (BEM) is introduced to calculate ultra-high quality factors (Q) of whispering-gallery modes (WGMs) by studying the Poyting vector. In traditional numerical method, Q can be obtained through the formula Q = -Re(k)/2Im(k) by solving the wavenumber (k) of resonances, such that the precision of Q is determined by the wavenumber k. On the other...
We report experimental study on the evolution of the emission mechanism by using a phase-space imaging technique based on the local angular momentum conservation in emission process in a chaotic optical microcavity as the cavity deformation corresponding to nonintegrability increases. In the regime of weak deformation, we could image the output beam being emitted tangentially from a location at a...
In this paper, the admission control policies proposed for Cross-Protect routers in Flow-Aware Networks (FAN) are compared. A Multilayer FAN (MFAN) architecture defines policies to decide which flows are more suitable to be transmitted through the optical layer in case of congestion. In this work, we evaluate how to include the information of such policies in the admission control process. As a result...
The statistics of ldquoequivalentrdquo differential phase (EDP) of differential quadrature phase-shift keying (DQPSK) systems is assessed numerically. It is shown that the EDP statistics is approximately Gaussian for a large range of system parameters. Thus, performance evaluation methods based on a Gaussian approximation for the EDP may be used. However, both the mean and variance of the Gaussian...
Doped Photonic Crystal Fiber (PCF) confining the fundamental mode in a small high-index core can exhibits parabolic evolution of chromatic dispersion with two zero-dispersion points and flat negative chromatic dispersion over O-Band, S-Band, C-Band and L-Band. A generally accepted view is that the zero-dispersion point can be governed by selecting the appropriate diameter of a core. It allows for...
Adaptation to changing conditions in the transmission medium is a particularly desired property in optically-routed networks due to their heterogeneous nature. Toward this goal, we propose in this paper rate-adaptive polarization multiplexed coded multilevel modulation schemes based on non-binary quasi-cyclic low-density parity-check (LDPC) codes and coherent detection. The proposed scheme can support...
In this paper, a ring laser configuration for fibre sensing applications based on highly erbium-doped fibres is studied. The proposed configuration uses fibre Bragg grating reflectors in order to select the emission wavelengths. The experimental results have demonstrated that the topology arranged in a hybrid serial-tree configuration offers excellent performances in terms of temporal laser stability...
Recently, we have demonstrated internal net gain with a bandwidth of 80 nm (1500 - 1580 nm) and 1533 nm peak gain of 2.0 dB/cm in Al2O3:Er3+ channel waveguides which were sputtered on silicon substrates and subsequently reactive ion etched. Based on measured spectroscopic parameters, rate-equation simulations predict gain of >20 dB throughout the entire telecom C-band for optimized waveguide lengths...
Multimode Interference (MMI) devices have found wide use in photonic integrated circuits as couplers, multiplexers, switches and filters, as well as performing other useful signal processing functions. In the past, first order design formulae for such devices have relied on using simplifying assumptions that are not very accurate. The designer typically then uses repeated field simulations, varying...
Dynamic behavior caused by Brillouin scattering in Raman fiber amplifiers is studied. Modes of self-pulsation steady state oscillations are found. Their dependence on amplification scheme is demonstrated.
The design of both active and passive micro/nano-sphere systems is performed by optimizing their sizes, spatial distribution and the other physical and geometrical parameters. In particular, rare earth doped spherical particles are designed in order to obtain distributed and highly efficient light sources for active sensors. The lasing characteristics of active silica glass microsphere are numerically...
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