2.5-Gb/s Transmission over 50 km with a 1.3-mu m vertical-cavity surface-emitting laser

We demonstrate error-free 50-km transmission at 2.5 Gb/s over standard sing le-mode fiber using an optically pumped 1.3-mum vertical-cavity surface-emi tting laser operating at 25 degreesC. No optical isolator or amplification was used in the transmission demonstration. System backreflection sensitivi ty measurements were conducted for various fiber distances and reflection f eedback levels. The results indicate a transmission power penalty of 0.1 dB at a bit-error rate of 10(-9) for a reflection feedback level of -25 dB wi th the reflection originating at 5 m.