First experimental demonstration of 6Gb/s real-time optical OFDM transceivers incorporating channel estimation and variable power loading

The fastest ever 6Gb/s real-time FPGA-based optical orthogonal frequency division multiplexing (OOFDM) transceivers utilizing channel estimation are experimentally demonstrated, for the first time, with variable power loading being incorporated to effectively compensate for the rapid system frequency response roll-off effect. The implemented transceivers are constructed entirely from off-the-shelf components and incorporate crucial functionalities of on-line performance monitoring and live optimization of key parameters including signal clipping, subcarrier power and operating conditions of directly modulated DFB lasers (DMLs). Real-time end-to-end transmission of a 6Gb/s 16-QAM-encoded OOFDM signal over 300m OM1 multi-mode fiber with a power penalty of 0.5dB is successfully achieved in an intensity-modulation and direct-detection system employing a DML. (C) 2009 Optical Society of America