Abstract

Optical systems relying on launching high optical powers into fiber, such as repeaterless transmission systems are typically forced to employ artificial broadening of the spectrum to avoid Stimulated Brillouin Scattering [e.g. 1, 2]. Superimposing a small-signal sinusoid with a frequency of 5 kHz to 10 kHz onto the DC bias current of the laser diode is an efficient method for broadening the time-averaged optical spectrum [3]. Launch powers of up to 24 dBm, which have proven advantageous for maximizing the transmission distance of repeaterless systems, requires a spectral width on the order of 10 GHz [4]. This level of artificial broadening of the spectrum typically implies significant residual amplitude modulation, which translates into degradation of system performance.

© 1995 Optical Society of America