Relevant bibliographies by topics / Directional Coupler Modulator

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  1. Journal articles
  2. Dissertations / Theses
  3. Books
  4. Book chapters
  5. Conference papers

Academic literature on the topic 'Directional Coupler Modulator'

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Published: 14 March 2023

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Journal articles on the topic "Directional Coupler Modulator"

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Yu, M., and A. Gopinath. "Seventeen-GHz directional coupler optical modulator." IEEE Transactions on Microwave Theory and Techniques 43, no. 9 (1995): 2198–202. http://dx.doi.org/10.1109/22.414564.

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Thaniyavarn, S. "Modified 1×2 directional coupler waveguide modulator." Electronics Letters 22, no. 18 (1986): 941. http://dx.doi.org/10.1049/el:19860641.

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Bhowmik, Tanmay, and Debabrata Sikdar. "Parallel directional coupler based dual-polarization electro-absorption modulator using epsilon near-zero material." Journal of Physics D: Applied Physics 55, no. 13 (December 31, 2021): 135107. http://dx.doi.org/10.1088/1361-6463/ac4455.

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Abstract Electro-optical modulation, where a radio frequency signal can be encoded in an optical field, is crucial to decide the overall performance of an integrated photonics system. Due to the growing internet penetration rate worldwide, polarization-division-multiplexing (PDM) technique has emerged to increase the link capacity, where polarization-independent modulators are desirable to reduce system complexity. In this study, we propose a novel parallel directional coupler based dual-polarization electro-absorption modulator based on epsilon-near-zero (ENZ) material. The proposed design is capable of independent and synchronized modulation of two fundamental modes viz. transverse magnetic (TM) and transverse electric (TE) mode of a standard silicon (Si) rib waveguide. Indium-tin-oxide (ITO)–Si based two parallel hybrid plasmonic waveguides (HPW1 and HPW2) are placed such that fundamental TM (TE) mode of the input bus waveguide can be coupled to HPW1 (HPW2). The ENZ-state of ITO, acquired upon two independent electrical gating, enables large modulation depth by utilizing enhancement of electric field at the absorptive carrier accumulation layer. With a 27 μm active length, the extinction ratio (ER) of the proposed design is 10.11 dB (9.66 dB) for TM (TE) modulation at 1550 nm wavelength. This results in a 0.45 dB ER-discrepancy and indicates the polarization-insensitive nature of the modulator. The insertion losses and modulation bandwidths of our design are less than 1 dB and more than 100 GHz, respectively, for both polarizations over the entire C-band of wavelength. The proposed design can find potential applications in the PDM-enabled integrated photonics systems and high speed optical interconnections at data center networks.
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Anwar, N., C. Themistos, B. M. A. Rahman, and K. T. V. Grattan. "Design considerations for an electrooptic directional coupler modulator." Journal of Lightwave Technology 17, no. 4 (April 1999): 598–605. http://dx.doi.org/10.1109/50.754789.

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Hayashi, Hideki, and Kunio Tada. "GaAs traveling‐wave directional coupler optical modulator/switch." Applied Physics Letters 57, no. 3 (July 16, 1990): 227–28. http://dx.doi.org/10.1063/1.103723.

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Yu-Chueh Hung and H. R. Fetterman. "Polymer-based directional coupler modulator with high linearity." IEEE Photonics Technology Letters 17, no. 12 (December 2005): 2565–67. http://dx.doi.org/10.1109/lpt.2005.859491.

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Yu-Chueh Hung, Soeng Ku Kim, H. Fetterman, Jingdong Luo, and A. K.-Y. Jen. "Experimental Demonstration of a Linearized Polymeric Directional Coupler Modulator." IEEE Photonics Technology Letters 19, no. 21 (November 2007): 1762–64. http://dx.doi.org/10.1109/lpt.2007.905661.

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Tahersima, Mohammad H., Zhizhen Ma, Yaliang Gui, Shuai Sun, Hao Wang, Rubab Amin, Hamed Dalir, Ray Chen, Mario Miscuglio, and Volker J. Sorger. "Coupling-enhanced dual ITO layer electro-absorption modulator in silicon photonics." Nanophotonics 8, no. 9 (August 14, 2019): 1559–66. http://dx.doi.org/10.1515/nanoph-2019-0153.

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AbstractElectro-optic signal modulation provides a key functionality in modern technology and information networks. Photonic integration has not only enabled miniaturizing photonic components, but also provided performance improvements due to co-design addressing both electrical and optical device rules. The millimeter to centimeter footprint of many foundry-ready electro-optic modulators, however, limits density scaling of on-chip photonic systems. To address these limitations, here we experimentally demonstrate a coupling-enhanced electro-absorption modulator by heterogeneously integrating a novel dual-gated indium-tin-oxide phase-shifting tunable absorber placed at a silicon directional coupler region. This concept allows utilizing the normally parasitic Kramers-Kronig relations here in an synergistic way resulting in a strong modulation depth to insertion loss ratio of about 1. Our experimental modulator shows a 2 dB extinction ratio for a just 4 μm short device at 4 V bias. Since no optical resonances are deployed, this device shows spectrally broadband operation as demonstrated here across the entire C-band. In conclusion, we demonstrate a modulator utilizing strong index change from both real and imaginary parts of active material enabling compact and high-performing modulators using semiconductor near-foundry materials.
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Tavlykaev, R. F., and R. V. Ramaswamy. "Highly linear Y-fed directional coupler modulator with low intermodulation distortion." Journal of Lightwave Technology 17, no. 2 (1999): 282–91. http://dx.doi.org/10.1109/50.744238.

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Laliew, C., S. W. Lovseth, Xiaobo Zhang, and A. Gopinath. "A linearized optical directional-coupler modulator at 1.3 /spl mu/m." Journal of Lightwave Technology 18, no. 9 (September 2000): 1244–49. http://dx.doi.org/10.1109/50.871701.

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Dissertations / Theses on the topic "Directional Coupler Modulator"

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Hung, Yu-Chueh. "Linearized electrooptic polymeric directional coupler modulator." Diss., Restricted to subscribing institutions, 2007. http://proquest.umi.com/pqdweb?did=1383481091&sid=1&Fmt=2&clientId=1564&RQT=309&VName=PQD.

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Laliew, Chanin. "A synthesized electrooptic directional-coupler modulator at 1300-nanometer wavelength with low switching voltage /." Diss., ON-CAMPUS Access For University of Minnesota, Twin Cities Click on "Connect to Digital Dissertations", 2002. http://www.lib.umn.edu/articles/proquest.phtml.

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GHOMASHI, MOHAMMADAMIN. "Multiphysics Simulation of Electro-optic Modulators Based on Plasmonic Waveguides." Doctoral thesis, Politecnico di Torino, 2022. http://hdl.handle.net/11583/2970992.

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Daniel, Hani S. "Electro-optic waveguide modulators based on the coaxial directional coupler." Thesis, Imperial College London, 1987. http://hdl.handle.net/10044/1/38277.

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Costa, Marcos Benedito Caldas. "AnÃlise NumÃrica do Acoplador Duplo NÃo-Linear Baseado em Fibras de Cristais FotÃnicos (NLDC-PCF) Operando com PAM e PWM para ObtenÃÃo de Portas LÃgicas." Universidade Federal do CearÃ, 2013. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=9147.

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CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior
Neste trabalho, apresentamos uma anÃlise numÃrica para a obtenÃÃo de portas lÃgicas totalmente Ãptica baseada em um acoplador direcional nÃo-linear simÃtrico (NLDC) em fibras de cristal fotÃnico (PCF). O projeto mais comumente usado para o NLDC-PCF à uma fibra holey, utilizada neste trabalho, em que a seÃÃo transversal à uma matriz periÃdica de buracos de ar que se prolonga por todo o comprimento da fibra, operando com dois pulsos de luz ultracurtos na forma de sÃlitons, de duraÃÃo mÃnima de 100fs (femtosegundos). Investigamos dois formatos de modulaÃÃo por pulsos, a modulaÃÃo por amplitude de pulso (PAM) na modalidade de chaveamento de mudanÃa de amplitude (ASK) e a modulaÃÃo por largura de pulso (PWM) para obter portas lÃgicas no NLDC-PCF duplo simÃtrico. Avaliamos o efeito resultante de um incremento no parÃmetro codificaÃÃo PAM (ε) e PWM (w), considerando a dispersÃo de segunda ordem (β2), a dispersÃo de terceira ordem (β3) e efeitos nÃo-lineares, tais como: SPM (Self Phase Modulation), SS (Self-Steepening) e IRS (lntrapulse Raman Scattering) em uma configuraÃÃo sem perdas. Os nossos resultados indicam que à possÃvel obter operaÃÃes lÃgicas utilizando um controle de fase entre os pulsos de entrada.
We present a numerical analysis for obtaining all-optical logic gates based on a nonlinear directional coupler symmetric (NLDC) based on photonic crystal fibers (PCF). The most commonly used to project the NLDC-PCF is a holey fiber, used here in cross section which is a periodic array of air holes extending through the length of the fiber, using two ultrashort light pulses in form of solitons, the minimum duration of 100fs (femtoseconds). We investigated two forms of modulation pulse, pulse amplitude modulation (PAM) in the form of amplitude shift keying (ASK) modulation and pulse width modulation (PWM) for logic gate NLDC-PCF symmetrical double. We evaluated the effect resulting from an increase in the offset parameter encoding PAM (ε) and PWM (w), considering the second order dispersion (β2), the third order dispersion (β3) and non-linear modulation effects SPM (Self Phase Modulation), SS (Self-Steepening) and IRS (lntrapulse Raman Scattering) in a configuration without loss. Our results indicate that logical operations can be obtained using a phase control between the input pulses.
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Bastos, Agliberto Melo. "Estudo de acopladores de fibra Ãptica tradicional e de cristal fotÃnico e aplicaÃÃes: geraÃÃo de portas lÃgicas e sensor de corrente elÃtrica." Universidade Federal do CearÃ, 2015. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=15236.

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FundaÃÃo de Amparo à Pesquisa do Estado do CearÃ
Apresentamos neste trabalho, uma analise numÃrica para obtenÃÃo de portas lÃgicas em acoplador nÃo-linear simÃtrico (NLDC) em fibras de cristal fotÃnico (PCF), que em sua secÃÃo transversal à formada com matriz periÃdica de buracos de ar, operando em pulso de luz ultracurtos na forma de sÃlitons, com duraÃÃo de 100fs (fentosegundos). Foram investigados formatos dos pulsos em modulaÃÃo por amplitude de pulso (PAM), com chaveamento de mudanÃa de amplitude (ASK), com objetivo de obter portas lÃgicas no NLDC-PCF triplo planar simÃtrico. Neste trabalho usamos acopladores duplos de fibra Ãptica na constituiÃÃo de um InterferÃmetro Mach-Zenhder para construir um sensor de corrente, sua funcionalidade à aplicada para investigar a qualidade da corrente alternada, quer seja na geraÃÃo, transmissÃo ou distribuiÃÃo de energia elÃtrica. Como o interferÃmetro de Mach-Zenhder usa um agente mecÃnico, usaremos o mesmo agente para construir o sensor de corrente constituÃdo de um PiezelÃtrico. Ao fazer o comparativo dos dois sensores, podemos destinar sua usabilidade em diferenciados consumidores
In this work, a numerical analysis to obtain gates in coupler symmetrical nonlinear (NLDC) in photonic crystal fibers (PCF), which in cross section is formed with periodic array of air holes, operating in light pulse ultrashort as solitons, lasting 100fs (fentosegundos). The pulses in pulse amplitude modulation formats were investigated (WFP), with amplitude shift keying (ASK), in order to obtain logic gates in the triple NLDC PCF-planar symmetrical. In this paper we use double couplers fiber optic in setting up a Mach-Zenhder Interferometer to build a current sensor, its functionality is applied to investigate the quality alternating current, whether in the generation, transmission or distribution of electricity. Since the interferometer of Mach-Zenhder uses a mechanical agent, agent will use the same for constructing the current sensor constituted of a piezoelectric. In making the comparison of the two sensors, we can allocate its usability in different consumers
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Kuo, Yu-zheng, and 郭祐禎. "Photonics Ultra-Wide-Band Doublet Pulse Based on Tapered Directional Coupler Integrated Electroabsorption Modulator." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/57478532747265543163.

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碩士
國立中山大學
光電工程學系研究所
99
Ultra Wide Band (UWB) is a short-pulse signal which has extremely potential in wireless communication system due to the advantages of high data rate, better immunity to multipath fading, wide bandwidth, and high capability. According to the Federal Communications Commission (F.C.C.), UWB only can be transmitted in short distance of a few to tens of meters due to low power density (-41.3dBm/MHz). However, optical fiber has low loss and cost and wide bandwidth, so it can be achieved in wide area network. In this work, we propose a novel method to generate optical UWB doublet pulse without complicated setup. When electroabsorption modulator (EAM) integrating a taper optical directional coupler (TODC) was applied field, the transmission loss and coupling would change resulting from the absorption coefficient and effective index of active waveguide with the applied field. So, we used a single mode fiber collecting the power after the device, we could get the valley shape transfer function. Using the transfer function of electro-absorption modulator (EAM) integrating TODC we inject a Gaussian pulse into the EAM in the range of valley shape, and it can transform an electrical pulse into optical UWB doublet pulse by acceptable operating point. Therefore, the optical signals could be transmitted in optical fiber so that it can reduce loss of the electro-optic transformation. Experimentally, the full wave at half maximum of doublet pulse, 10dB bandwidth, fractional bandwidth were 75ps, 7.5GHz, 125%, respectively, and power density was less than -41.3dBm/MHz. These were all meeting the F.C.C. standard. In the future, we will use long distant optical fiber to transmitted UWB signal, and compare with different distance. Finally, we will check the UWB signal can be transmitted in optical fiber to achieve wide range signal transmission by bit error rate test.
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chun, che-chang, and 張哲準. "Voltage Control Refractive Index Vertical Directional Coupler For Integrating Spot Size Converter And Electroabsorption Modulator." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/45562765560392704616.

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碩士
國立中山大學
光電工程研究所
96
Abstract Optical spot-size converter (SSC) is an essential element in the opto-electronic integrated circuit because of its direct coupling to single-mode optical fiber, low-cost from the misalignment issue in package. By the tapered waveguide structure, SSC offers a capability to transfer an elliptical optical mode of optical waveguide to single-mode fiber matched mode, allowing the independence of device design from the coupling issue. However, the conversion efficiency of SSC is strongly reliant on tapered waveguide structure, material index, and also excitation wavelengths, restricting design and fabrication of SSC. In order to enhance the reliability on SSC fabrication, a voltage-controllable SSC integrated with electroabsorption modulator (EAM) is designed and fabricated. The tapered waveguide processing is based on the selective undercut wet-etching on InGaAsP-material system. The active waveguide width of EAM is 3.5μm, where the tapered waveguide widths is ranged from 1.7μm to 3.5μm. The transferred optical waveguide (passive waveguide) is 8μm wide. By adjusting the voltage of tapered waveguide, coupling efficiency is enhanced by 2dB from 1560nm to 1570nm. A reliable SSC-integrated EAM with -12dB of insertion loss, extinction ratio of 22dB is demonstrated. By extracting the index change from Fabry-Perot optical mode of waveguide, index variation from reverse bias is in the order of 10-3, consistent with the calculation based on Kramer-Kronig model.
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Lee, Beom Suk 1974. "Novel EO polymer-based micro- and nano photonic devices for analog and digital communications." Thesis, 2011. http://hdl.handle.net/2152/ETD-UT-2011-05-2673.

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Polymer-based electro-optical modulators are, generally, applicable to many fields but their applications to analog optical links and silicon photonic integrated circuits are specifically emphasized in this dissertation. This dissertation aims to improve the linearity characteristics of polymer-based electro-optic modulators for their practical application in high speed analog optical links. Domain-inversion technique is employed to linearize a two-section Y-fed directional coupler modulator. The spurious free dynamic range as high as 119dB/Hz2/3 has been demonstrated with 11dB enhancement over the conventional Mach-Zehnder modulator at low frequency. For high speed modulation, a traveling wave electrode with low RF loss and large bandwidth is designed and installed in a linearized Y-fed directional coupler modulator. The spurious free dynamic range has been measured in the range of 110±3dB/Hz2/3 at 2~8GHz frequency. For digital application of polymer-based electro-optic modulators, a hybrid silicon photonic crystal waveguide modulator was investigated with focus on size-reduction and electro-optic efficiency enhancement. The slow group velocity of photonic crystal waveguides promises two orders of magnitude size-reduction in device footprint compared with the conventional strip waveguide. Infiltration of an electro-optic polymer into the slot waveguide can infuse silicon with nonlinear optical properties. To actualize these benefits of a hybrid silicon photonic crystal waveguide modulator, nano-fabrication process was developed and optimized in this work.
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Zhou, Qingjun. "Electro-optic modulators based on polymeric Y-fed directional couplers." Thesis, 2004. http://hdl.handle.net/2152/1444.

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Books on the topic "Directional Coupler Modulator"

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Kim, Chang Min. Traveling-wave LiNbo3 optical modulator using Y-branch directional coupler. 1989.

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Book chapters on the topic "Directional Coupler Modulator"

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Zhixun, Liang, Yi Yunfei, Lin Fang, and Fan Yuanyuan. "Silicon Electro-optic Modulator for Photonic Ring Network On-Chip Based on Dual ITO Layer Directional Coupler." In Proceedings of the 11th International Conference on Computer Engineering and Networks, 903–8. Singapore: Springer Singapore, 2021. http://dx.doi.org/10.1007/978-981-16-6554-7_97.

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Rasch, A., M. Rottschalk, and W. Karthe. "Optimization of Ti:LiNbO3 Directional Couplers and Their Application to a Mach-Zehnder Interferometer Modulator." In Springer Series in Optical Sciences, 232–35. Berlin, Heidelberg: Springer Berlin Heidelberg, 1985. http://dx.doi.org/10.1007/978-3-540-39452-5_45.

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Ziemann, Ulf. "Enhancement of neuroplasticity by drug therapy." In Oxford Textbook of Neurorehabilitation, edited by Volker Dietz, Nick S. Ward, and Christopher Kennard, 221–36. Oxford University Press, 2020. http://dx.doi.org/10.1093/med/9780198824954.003.0017.

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This chapter reviews effects of central nervous system (CNS) active drugs specifically on activity-dependent plasticity and learning. The rationale for choosing this focus is the existing evidence that CNS active drugs have an impact on rehabilitation success after stroke to a relevant extent only if coupled with task-specific practice. This chapter reviews pharmacological modulation of stimulation-induced long-term potentiation (LTP) in animal and human studies because synaptic plasticity in the form of LTP is a basic mechanism of learning and memory processes. Next, the chapter reviews the evidence of CNS active drugs on learning in animal and human studies. In the third part, the impact of CNS active drugs on neurorehabilitation of stroke patients is surveyed and the translational cascade from basic research to clinical studies is described. Finally, limitations of the current studies, open questions, and future directions are discussed. This chapter demonstrates significant impact of neuropharmacology on activity-dependent plasticity and learning.
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Ziemann, Ulf. "Enhancement of neuroplasticity by drug therapy." In Oxford Textbook of Neurorehabilitation, 193–208. Oxford University Press, 2015. http://dx.doi.org/10.1093/med/9780199673711.003.0017_update_001.

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This chapter reviews effects of CNS active drugs specifically on activity-dependent plasticity and learning. The rationale for choosing this focus is the existing evidence that CNS active drugs have an impact on rehabilitation success after stroke to a relevant extent only if coupled with task-specific practice. This chapter reviews pharmacological modulation of stimulation induced long-term potentiation (LTP) in animal and human studies because synaptic plasticity in the form of LTP is a basic mechanism of learning and memory processes. Next, the chapter reviews the evidence of CNS active drugs on learning in animal and human studies. In the third part, the impact of CNS active drugs on neurorehabilitation of stroke patients is surveyed and the translational cascade from basic research to clinical studies is described. Finally, limitations of the current studies, open questions and future directions are discussed. This chapter demonstrates significant impact of neuropharmacology on activity-dependent plasticity and learning.
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Katurji, Marwan, Bob Noonan, Jiawei Zhang, Andres Valencia, Benjamin Shumcher, Jessica Kerr, Tara Strand, Grant Pearce, and Peyman Zawar-Reza. "Atmospheric turbulent structures during shrub fires and implications for flaming zone behavior." In Advances in Forest Fire Research 2022, 1397–407. Imprensa da Universidade de Coimbra, 2022. http://dx.doi.org/10.14195/978-989-26-2298-9_212.

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Wildfires propagate across vegetated canopies exhibiting complex spread patterns. Wind gusts at the fire-front extend/intensify flames and direct convective heating towards unburnt fuels resulting in rapid acceleration of spread. This behavior could be modulated by ambient atmospheric boundary layer wind turbulence. Our aim is to characterize ambient turbulence over gorse shrub experimental burns and explore how this contributes to fire behavior. Developing coupled fire-atmosphere numerical models capable of resolving most turbulent energy scales is important for understanding rapid and small-scale dynamics. However, it is equally as important to design fire-burn experiments that allow for simultaneous measurements of fire behavior and atmospheric turbulence covering a range of the turbulent spectra. We have completed six experimental burns (24-hectares) in Rakaia, New Zealand under varying wind speed and direction and atmospheric stability regimes. The ignition process ensured a fire-line propagating through dense gorse bush (1m high). Two 30m high sonic anemometer towers measured turbulent wind velocity (20Hz) at six different height levels. Visible imagery was captured for all burns by cameras mounted on Un-crewed Aerial Vehicles (UAV) at 200m AGL. Using wavelet decomposition, we identified different turbulent scales that varied relative to height above vegetation and boundary layer thermal regimes. Quadrant analysis identified statistical distribution of atmospheric sweeps (downbursts of turbulence towards vegetation) and ejections (detachment of turbulence from vegetation). Discrete analysis of sweep/ejection events revealed their temporal and spatial scales and tracked their progression as the flaming zone approached the towers. Undergoing work aims to discern these interactions with observed fire sweeps from aerial imagery by applying image velocimetry techniques and sweep structure tracking
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Kennel, Charles F. "The Geosynchronous Substorm." In Convection and Substorms. Oxford University Press, 1996. http://dx.doi.org/10.1093/oso/9780195085297.003.0016.

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The reconnection model of substorms deals with the large-scale changes in the structure of the magnetosphere and tail as convection intensifies following a sudden increase in the dayside reconnection rate. The model has difficulty making statements relevant to the small scales that characterize auroral onset. However, there has been considerable progress in assembling high-resolution observations of the events in space that now appear to be tightly coupled to the dramatic auroral events that first defined the term substorm. We will call this clear and consistent ensemble the geosynchronous model of substorms, since most of it was first conceived from observations made on geostationary spacecraft. We will also include in this ensemble the recent observations made using the quasigeostationary spacecraft, AMPTE/CCE, and so, by the geosynchronous substorm, we really mean the substorm as it appears on the earth's nightside typically between 6 and, say, 10 RE downtail. The earth’s magnetic field at geosynchronous orbit is about 100 nT, some three times larger than in the tail lobes. Study of quiet field intervals singles out the dependence of the geosynchronous field on solar wind dynamic pressure, since the modulation due to changes in the direction of the interplanetary field is presumably negligible during quiet conditions. The periodic variations in the quiet field depend on local time, season, and orientation of the earth’s dipole axis relative to spacecraft location (McPherron and Barfield, 1980; Rufenach et al., 1992). Superposed on the quiet field are perturbations up to about 50 nT due to several magnetospheric current systems, including the magnetopause current, the ring current, and the cross-tail current; the most striking are due to changes in the cross-tail current system. Observations from geosynchronous orbit were the first to indicate that the nightside magnetic field becomes more “tail-like” during substorm growth phase, and more dipolar during the expansion phase. This simple observation is the foundation on which today’s elaborate geosynchronous substorm model rests. The geosynchronous field becomes progressively more “tail-like” as the cross-tail current system intensifies and/or moves earthward during the substorm growth phase (McPherron et al., 1975; Coleman and McPherron, 1976; McPherron, 1979; Kauffmann, 1987).
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Conference papers on the topic "Directional Coupler Modulator"

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Chang, William S. C., Mark L. Farwell, and Zong Qi Lin. "Directional coupler modulator with high linearity." In Beijing - DL tentative, edited by Sui-Sheng Mei and Bingkun Zhou. SPIE, 1993. http://dx.doi.org/10.1117/12.144153.

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Thaniyavarn, Suwat. "Self-Biased 1X2 Modified Directional Coupler Modulator." In Technical Symposium Southeast, edited by Shi-Kay Yao. SPIE, 1987. http://dx.doi.org/10.1117/12.940710.

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Khanna, Trishna, and Deepak Bhatia. "MEMS based optical phase modulator using directional coupler." In 2017 IEEE International Conference on Power, Control, Signals and Instrumentation Engineering (ICPCSI). IEEE, 2017. http://dx.doi.org/10.1109/icpcsi.2017.8392259.

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Sherif, S. M., L. A. Shahada, and M. Swillam. "Silicon nanowires organic hybrid modulator based on directional coupler." In 2016 Photonics North (PN). IEEE, 2016. http://dx.doi.org/10.1109/pn.2016.7537963.

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Khan, M. Nisa, Anand Gopinath, and Julian P. G. Bristow. "Velocity matched traveling wave directional coupler optical modulator in AlGaAs/GaAs." In Integrated Photonics Research. Washington, D.C.: Optica Publishing Group, 1991. http://dx.doi.org/10.1364/ipr.1991.thg5.

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The design for a new velocity matched traveling wave directional coupler modulator (DCM) in AlGaAs/GaAs material is proposed. The DCM characteristics are compared with those of the n-i-n modulator proposed by Kim et al.1 and the GaAs superstate modulator proposed by Nees et al2 In this paper, velocity matching in the DCM is achieved by covering the modulator and its electrode structure with a dielectric material of high dielectric constant which reduces the micro wave phase velocity to match the lightweight velocity. The dielectric materials used for the velocity matching analysis are alumina (Al2O3) and tantalum pentoxide (Ta2O5), whose relative dielectric constants at microwave frequencies are 10.0 and 27.0, respectively. The optical and microwave characteristics of the modulator are analyzed using the effective index method (EIM) and the finite difference method (FDM) repectively.
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Thaniyavarn, Suwat. "A Modified 1x2 Directional Coupler Modulator With Low Drive Voltage." In Cambridge Symposium-Fiber/LASE '86, edited by O. G. Ramer and Paul Sierak. SPIE, 1987. http://dx.doi.org/10.1117/12.937439.

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Hung, Yu-Chueh, SeongKu Kim, Harold R. Fetterman, Jingdong Luo, and Alex Jen. "Demonstration of Polymer-based Directional Coupler Modulator with High Linearity." In CLEO 2007. IEEE, 2007. http://dx.doi.org/10.1109/cleo.2007.4452710.

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8

Marsh, John A., Sriram Sriram, Anand Gopinath, Ross Schermer, Jaesang Oh, Stuart Kingsley, and Andrea Pollick. "Linearized electro-optic directional coupler modulator in stoichiometric lithium niobate." In Optical Science and Technology, the SPIE 49th Annual Meeting, edited by Edward W. Taylor. SPIE, 2004. http://dx.doi.org/10.1117/12.563068.

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9

Ashley, Paul R., and William S. C. Chang. "Linearization technique for a guided-wave electrooptic Bragg modulator." In Integrated and Guided Wave Optics. Washington, D.C.: Optica Publishing Group, 1986. http://dx.doi.org/10.1364/igwo.1986.thcc12.

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Abstract:
Many types of optical intensity modulator have a transfer curve which approximates a sinusoidal function. These include Bragg modulators of both the acoustooptical and electrooptical varieties.1 Also included are the Mach-Zehnder and directional coupler electrooptical modulators.2 For most analog applications a linear transfer curve is desired. Using a Fourier analysis, it is possible to generate any given transfer curve shape with combinations of properly chosen sinusoidal components. Therefore, by combining harmonically related modulator elements, a triangular transfer curve shape can be created. Demonstrated here is use of the third harmonic to extend the linear range of a Bragg-type electrooptic modulator in the planar waveguide. It is possible to extend this technique to the other types of modulator mentioned as well. Based on a straight line curve fit, a deviation of the output intensity of less than ±1 % from the linear voltage intensity relationship has been observed over a 97% modulation range. This was accomplished while maintaining a high efficiency with 7.2 V for complete modulation.
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10

Khan, M. Nisa. "High-bandwidth velocity-matched optical directional coupler modulator in AlGaAs/GaAs." In Integrated Optoelectronics for Communication and Processing. SPIE, 1992. http://dx.doi.org/10.1117/12.2321810.

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