Sub-cycle QAM modulation for VCSEL-based optical fiber links

Tien-Thang Pham, Roberto Rodes Lopez, Jesper Bevensee Jensen, Connie J. Chang-Hasnain, Idelfonso Tafur Monroy

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QAM modulation utilizing subcarrier frequency lower than the symbol rate is both theoretically and experimentally investigated. High spectral efficiency and concentration of power in low frequencies make sub-cycle QAM signals attractive for optical fiber links with direct modulated light sources. Real-time generated 10-Gbps 4-level QAM signal in a 7.5-GHz bandwidth utilizing subcarrier frequency at a half symbol rate was successfully transmitted over 20-km SMF using an un-cooled 1.5-μm VCSEL. Only 2.5-dB fiber transmission power penalty was observed with no equalization applied.
Original languageEnglish
JournalOptics Express
Issue number2
Pages (from-to)1830-1839
Publication statusPublished - 2013

Bibliographical note

This paper was published in Optics Express and is made available as an electronic reprint with the permission of OSA. The paper can be found at the following URL on the OSA website: Systematic or multiple reproduction or distribution to multiple locations via electronic or other means is prohibited and is subject to penalties under law.


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