Increasing dispersion tolerance of 10 Gbit/s directly modulated lasers using optical filtering

In the paper the effect of optical filtering of the chirped signal emitted by directly modulated laser on the dispersion tolerance is presented. It is demonstrated that positioning the central optical frequency of the laser on the rising slope of the narrowband optical filter (either band-pass or band-stop) with the roll-off around 5 dB/GHz allows tolerating up to 1700 ps/nm of dispersion at 10 Gbit/s data rate. The presented method, in contrast to standard dispersion compensating schemes, does not require any adjustment to the particular dispersion of the fibre link.