Summary
International Technical Conference on Circuits/Systems, Computers and Communications
2016
Session Number:T3-1
Session:
Number:5115
Unipolar Multicarrier Modulation for Optical Wireless Communications with Intensity Modulation and Direct Detection
Poompat Saengudomlert ,
pp.-
Publication Date:2016/7/10
Online ISSN:2188-5079
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Summary:
Optical wireless communications (OWC) has recently gained a lot of attention in the form of visible light communications (VLC). For low-cost system implementations, light emitting diodes (LEDs) are typically used as light sources. Light emitted from LEDs is non-coherent, and hence intensity modulation (IM) is used at LED-based transmitters. Accordingly, power detection or direct detection (DD) is used at receivers. The use of IM/DD requires that data signals are unipolar, i.e., non-negative, making conventional modulation schemes based on bipolar signals not applicable. This tutorial discusses unipolar modulations for OWC with IM/DD. The focus will be on multicarrier modulation, more specifically orthogonal frequency division multiplexing (OFDM), since it is more appropriate than single-carrier modulation for high data rates.