Reduction of the chromatic dispersion and chirping effects by using an injection-locked and directly intensity-modulated Fabry-Perot laser in point-to-point optical access networks

We present recent improvements achieved for two important transmission parameters—dispersion, induced by the optical fiber, and the chirp parameter of the laser source—in a directly modulated system based on an injection-locked and directly modulated Fabry–Pérot laser diode for high-speed optical access networks with a point-to-point topology. Measurements in the 20-GHz range of the frequency response for distances up to 35 km are conducted by carefully adjusting the optical power and frequency detuning of the distributed master laser in the central office, thereby overcoming the problem of chromatic dispersion in high-speed optical access. Moreover, the enhancements make it possible to increase the transmission distance when a 1550-nm Fabry–Pérot laser is used as the light source in the central office of a point-to-point optical access network by distributing the seed light into numerous downstream lasers. This improvement to the injection-locked Fabry–Pérot laser is expected to extend the length of already-built, fiber-to-the-home, point-to-point networks with a simple upgrade in the central office without prejudicing the terminal equipment.