123 research outputs found

    10 Mb/s visible light transmission system using a polymer light-emitting diode with orthogonal frequency division multiplexing

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    We present a newly designed polymer light-emitting diode with a bandwidth of ∼350 kHz for high-speed visible light communications. Using this new polymer light-emitting diode as a transmitter, we have achieved a record transmission speed of 10 Mb/s for a polymer light-emitting diode-based optical communication system with an orthogonal frequency division multiplexing technique, matching the performance of single carrier formats using multitap equalization. For achieving such a high data-rate, a power pre-emphasis technique was adopted

    A 10 Mb/s visible light communication system using a low bandwidth polymer light-emitting diode

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    In this paper we experimentally demonstrate a 10 Mb/s error free visible light communications (VLC) system using polymer light-emitting diodes (PLEDs) for the first time. The PLED under test is a blue emitter with ∼600 kHz bandwidth. Having such a low bandwidth means the introduction of an intersymbol interference (ISI) induced penalty at higher transmission speeds and thus the requirement for an equalizer. In this work we improve on previous literature by implementing a decision feedback equalizer, rather than a linear equalizer. Considering 7% and 20% forward error correction codes, transmission speeds up to ∼12 Mb/s can be supported

    Books in Arabic Script

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    The chapter approaches the book in Arabic script as the indispensable means for the transmission of knowledge across Eurasia and Africa, within cultures and across cultural boundaries, since the seventh century ad. The state of research can be divided into manuscript and print studies, but there is not yet a history of the book in Arabic script that captures its plurilinear development for over fourteen hundred years. The chapter explores the conceptual and practical challenges that impede the integration of the book in Arabic script into book history at large and includes an extensive reference list that reflects its diversity. The final published version was slightly updated, and includes seven illustrations of six Qurans from the holdings of Columbia University Libraries, four manuscripts and two printed versions. Moreover, the illustrations are images of historical artifacts which are in the public domain - despite Wiley's copyright claim

    The manuscript tradition of the Ethiopic Qalementos

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    = Witold Witakowski - Laura Lykowska (eds.), "Wälättä Yohanna. Ethiopian Studies in Honour of Joanna Mantel-Niecko on the Occasion of the 50th Year of Her Work at the Institute of Oriental Studies, Warsaw University
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