Open AccessReal-time demonstration of 128-QAM-encoded optical OFDM transmission with a 525bit/s/Hz spectral efficiency in simple IMDD systems utilizing directly modulated DFB lasers
Author(s) -
Xianqing Jin,
R. P. Giddings,
E. Hugues-Salas,
J. M. Tang
Publication year - 2009
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.17.020484
Subject(s) - optics , orthogonal frequency division multiplexing , quadrature amplitude modulation , modulation (music) , materials science , transmission (telecommunications) , spectral efficiency , qam , intensity modulation , laser , clipping (morphology) , single mode optical fiber , electronic engineering , optoelectronics , computer science , phase modulation , channel (broadcasting) , physics , telecommunications , phase noise , bit error rate , acoustics , engineering , linguistics , philosophy
The feasibility of implementing 128-QAM in off-the-shelf component-based real-time optical OFDM (OOFDM) transceivers incorporating advanced channel estimation, on-line performance monitoring and live parameter optimisation, is experimentally investigated, for the first time, in intensity-modulation and direct-detection (IMDD) single-mode fibre (SMF) and multi-mode fibre (MMF) transmission systems involving directly modulated DFB lasers. The highest ever spectral efficiency of 5.25bit/s/Hz is demonstrated successfully in the aforementioned simple systems. Experimental investigations show that, it is feasible to transmit 5.25 Gb/s 128-QAM-encoded OOFDM real-time signals over 25 km MetroCor(TM) SMFs and 500 m 62.5/125 microm OM1 MMFs. The impact of key parameters on the transmission performance of the real-time OOFDM transceivers with 128-QAM encoding are explored, based on which optimum signal clipping ratios are identified.