Optical transmission performance for DML considering laser chirp and fiber dispersion using AMOOFDM
Résumé
Fiber dispersion coupled with chirp parameter of the emitting laser impacts the optical transmission system performance. Fiber dispersion causes the propagating pulses to spread and overlap, and the chirp parameter produces a wavelength shift arising from the intensity variation of the directly modulated laser (DML). For optical transmission systems, orthogonal frequency division multiplexing (OFDM) modulation technique has proved to be an attractive approach to overcome optical fiber impairments in optical access networks as well as in long haul optical networks. Coupled with the Levin Campello bit-loading algorithm, adaptively modulated optical orthogonal frequency division multiplexing (AMOOFDM) optimizes the data rate by taking into consideration the channel quality of each subcarrier. This paper shows system performance for optical links starting with an optical back-to-back (BtB) connection and ending with 125 km of single mode fiber (SMF) with a fixed optical budget of 30 dB for all distances.