30 research outputs found
A Novel Approach for Designing Omnidirectional Slotted-Waveguide Antenna Array
This paper presents a novel design of a high-gain omnidirectional slotted-waveguide antenna array for 5G mm-wave applications. The structure is based on a circular waveguide filled with teflon for manipulating its dimension. It provides 12,1 dBi gain and omnidirectional coverage in the azimuth plane with only 1.3 dB deviation, which is ensured by making use of a twisting technique for proper placing the slots into the waveguide walls. A bandwidth of 1.61 GHz centered at 26.2 GHz has been numerically demonstrated
Applicability of low macrobending loss hollow-core PCF to FTTH applications
Fiber-To-The-Home (FTTH) technology has been significantly implemented in access networks, providing very high data rates transmission and a variety of digital content to subscribers. It involves an optical cable link being installed between the building entry point and each subscriber with the Multiple Dwelling Units (MDUs), i.e. flats and apartments. In other words, optical cable has to lie fairly straight to carry a strong signal, since typically is necessary to bend, twist and turn the lines in and out of tight corners without degrading the link connection. In this paper we propose the use of Hollow-Core Photonic Crystal Fiber (HC-PCF) for FTTH applications. It is presented an experimental analysis of the macrobending effects in a HC-PCF based on a comparison with traditional fibers and by following the ITU-T G.657B standard recommendations. We observe this fiber, with only 6.5 µm core, is bending loss insensitive, even at extremely small bending radius of 2 mm, in which it presents a loss of only 0.58 dB.251258Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Coordenação de Aperfeiçoamento de Pessoal de NÃvel Superior (CAPES
Optically controlled reconfigurable antenna for 5G future broadband cellular communication networks
A low-profile and ultra-wideband printed antenna with a 176% bandwidth
Abstract This work reports the development of a simple, low-profile and ultra-wideband printed antenna. The proposed antenna is based on a truncated ground plane and an impedance matching structure formed by a round junction and two chamfers; these modifications significantly increase the antenna frequency bandwidth compared to conventional microstrip antennas and ultra-wideband printed monopoles published in literature. An antenna prototype was fabricated using an Arlon DiClad 880 substrate with an electrical permittivity of 2.2. A bandwidth of 176% was attained at a central frequency of 14.9 GHz (ranging from 1.79 to 28.02 GHz). Numerical simulations and experimental results of the antenna's radiation pattern are also reported and exhibit good agreement. To the best of our knowledge, this is the widest bandwidth from a printed antenna that has been published in the literature
Material Characterization and Propagation Analysis of mm-Waves Indoor Networks
Abstract This paper reports detailed propagation analyses of mm-wave indoor networks based numerical simulations of the wireless coverage and measurements of the propagation coefficient at 28 and 38 GHz. Additionally, material characterization of typical buildings materials used in constructions are presented, including: common brick (with and without electrical installations); plaster walls; glazing, Eucatex panels; wooden doors. The computational simulations have been performed using Altair WinPropâ„¢ software in order to predict path loss in LOS (Line-of-Sight) and NLOS (Non-Line-of-Sight) environments. The obtained results contributes to the planning of the fifth Generation of mobile communications networks (5G), operating in mm-waves
Birefringence Properties Of Hybrid Photonic Crystal Fibers
We present a fabrication and an experimental investigation of the birefringent properties of a Highly Birefrigent Hybrid Photonic Crystal Fiber. Polarization dependent loss as high as 21 dB is experimentally obtained on the photonic bandgap edges. ©2009IEEE.804805Knight, J.C., Photonic Crystal Fibres (2003) Nature, 424, pp. 847-851. , AugustArismar Cerqueira Jr., S., Luan, F., Cordeiro, C.M.B., George, A.K., Knight, J.C., Hybrid photonic crystal fiber (2006) Optics Express, 14, pp. 926-931Arismar Cerqueira Jr., S., Cordeiro, C.M.B., Biancalana, F., Roberts, P.J., Hernandez-Figueroa, H.E., Brito Cruz, C.H., Hybrid photonic crystal fiber,Nonlinear interaction between two different photonic bandgaps of a Hybrid Photonic Crystal Fiber (2008) Optics Letters, 33. , SeptemberSchreiber, T., Stress-induced single-polarization single-transverse mode photonic crystal fiber with low nonlinearity (2005) Optics Express, 13, pp. 7621-763
Highly Birefringent Hybrid Photonic Crystal Fiber
The Hybrid Photonic Crystal Fiber is a novel type of microstructured fiber, in which for the first time, light was guided and manipulated simultaneously by two different prop- agation mechanisms: modified total internal reflection from an array of air holes and antiresonant reflection from a line of high-index inclusions. We present an experimental investigation of the birefringent properties of a Highly Birefrigent Hybrid Photonic Crystal Fiber.212681270Knight, J.C., Photonic crystal fibres (2003) Nature, 424, pp. 847-851. , AugustCerqueira Jr., A., Luan, S.F., Cordeiro, C.M.B., George, A.K., Knight, J.C., Hybrid photonic crystal fiber (2006) Opt. Express, 14, pp. 926-931Cerqueira, Jr.A., Cordeiro, S.C.M.B., Biancalana, F., Roberts, P.J., Hernandez-Figueroa, H.E., Brito Cruz, C.H., Nonlinear interaction between two different photonic bandgaps of a hybrid photonic crystal fiber (2008) Opt. Letters, 33. , SeptemberSchreiber, T., Stress-induced single-polarization single-transverse mode photonic crystal fiber with low nonlinearity (2005) Opt. Express, 13, pp. 7621-763
Second Harmonic Generation Of Cascaded Four-wave Mixing
It has been generated a 200-nm optical frequency comb at 1.5 μm by injecting two single-frequency lasers into highly nonlinear fibers by means of full nonlinear conversion into its second harmonic. Combs of optical frequencies with 100-nm (∼48 THz) bandwidths, centered at 790-800 nm and spaced by 0.8-1 nm (380-470 GHz) have been produced by second harmonic and multiple sum frequency generation simply by focusing into a 2-mm long nonlinear BIBO crystal. Conventional birefringence phase matching has been used in normal incidence configuration without tilting the crystal. ©2009IEEE.792795Udem, Th., Reichert, J., Holzwarth, R., Hänsch, T.W., Absolute Optical Frequency Measurement of the Cesium D1 Line with a Mode-Locked Laser (1999) Phys. Rev. Lett., 82, pp. 3568-3571Udem, T., Holzwarth, R., Hansch, T.W., Optical frequency metrology (2002) Nature, 416, pp. 233-237Ludlow, D., Zelevinsky, T., Campbell, G.K., Blatt, S., Boyd, M.M., De Miranda, M.H.G., Martin, M.J., Oates, C.W., Sr Lattice Clock at 1 × 10-16 Fractional Uncertainty by Remote Optical Evaluation with a Ca Clock (2008) Science, 319, pp. 1805-1808Lea, S.N., Limits to time variation of fundamental constants from comparisons of atomic frequency standards (2007) Rep. Prog. Phys., 70, pp. 1473-1523Goulielmakis, E., Yakovlev, V.S., Cavalieri, A.L., Uiberacker, M., Pervak, V., Apolonski, A., Kienberger, R., Krausz, F., Attosecond Control and Measurement: Lightwave Electronics (2007) Science, 317, pp. 769-775Baltuska, A., Udem, Th., Uiberacker, M., Hentschel, M., Goulielmakis, E., Gohle, Ch., Holzwarth, R., Krausz, F., Attosecond control of electronic processes by intense light fields (2003) Nature, 421, pp. 611-615Del'Haye, P., Schliesser, A., Arcizet, O., Wilken, T., Holzwarth, R., Kippenberg, T.J., Optical frequency comb generation from a monolithic microresonator (2007) Nature, 450, pp. 1214-1217Del'Haye, P., Arcizet, O., Schliesser, A., Holzwarth, R., Kippenberg, T.J., Full stabilization of a microresonator frequency comb (2008) Phys. Rev. Lett., 101, pp. 53903-53906Weber, H.G., Ludwig, R., Ferber, S., Langhorst, C.S., Kroh, M., Marembert, V., Boerner, C., Schubert, V., Ultrahigh-Speed OTDM-Transmission Technology (2006) J. Lightwave Technol., 24, pp. 4616-4627Pitois, S., Fatome, J., Millot, G., Generation of 160-GHz transform limited pedestal-free pulse train through multiwave mixing compression of a dual-frequency beat signal (2008) Opt. Lett., 27, pp. 1729-1731Pitois, S., Finot, C., Fatome, J., Sinardet, B., Millot, G., Generation of 20-GHz picosecond pulse trains in the normal and anomalous dispersion regimes of optical fibers (2006) Opt. Commun., 260, pp. 301-306A Cerqueira Jr., S., Chavez Boggio, J.M., Rieznik, A.A., Hernandez-Figueroa, H.E., Fragnito, H.L., Knight, J.C., Highly efficient generation of broadband cascaded four-wave mixing products (2008) Opt. Express, 16, pp. 2816-2828Fatome, J., Pitois, S., Millot, G., 20-GHz-to-1 GHz repetition rate pulse sources based on multiple four-wave mixing in optical fibers (2006) J. Quantum Electron., 42, pp. 1038-1046Cruz, F.C., Optical frequency combs generated by four-wave mixing in optical fibers for astrophysical spectrometer calibration and metrology (2008) Opt. Express, 16, pp. 13267-13275Xu, B., Coello, Y., Lozovoy, V.V., Harris, D.A., Dantus, M., Pulse shaping of octave spanning femtosecond laser pulses (2006) Opt. Express, 14, pp. 10939-10944Coello, Y., Xu, B., Nogueira, G.T., Cruz, F.C., Dantus, M., Asynchronous encrypted information transmission with sub-6 fs laser system at 2.12 GHz repetition rate (2008) Opt. Express, 16, pp. 15109-15114Jiang, Z., Leaird, D.E., Weiner, A.M., Line-by-line pulse shaping control for optical arbitrary waveform generation (2005) Opt. Express, 13, pp. 10431-10439Huand, D., Swanson, E.A., Lin, C.P., Schuman, J.S., Stinson, W.G., Chang, W., Hee, M.R., Fujimoto, J.G., Optical coherence tomography (1991) Science, 254, pp. 1178-1181Li, H., Ogusu, K., Dynamic behavior of stimulated Brillouin scattering in a single-mode optical fiber (1999) Jpn. J. Appl. Phys., 38, pp. 6309-6315Fatome, J., Pitois, S., Millot, G., 320/640 GHz high-quality pulse sources based on multiple four-wave mixing in highly nonlinear optical fibre (2005) Electron. Lett., 41, pp. 1391-1392Xiao, X., Yang, C., Gao, S., Miao, H., Analysis of ultrashort-pulse second-harmonic genera tion in both phase- And group-velocity-matched structures (2005) J. Quantum Electron., 41, pp. 85-93Nelson, L.E., Fleischer, S.B., Lenz, G., Ippen, E.P., Efficient frequency doubling of a femtosecond fiber laser (1996) Opt. Lett., 21, pp. 1759-1761Smith, A.V., SNLO Free Public Domain Software on Nonlinear Optics, , http://www.as-photonics.com/SNLO, Available atBoyd, G.D., Kleinman, D.A., Parametric Interactions of Focused Gaussian Light Beams (1968) J. Appl. Phys., 39, pp. 3597-363