George Fujitsu Limited Ishikawa

3.5-Tbit/s (43-Gbit/s /spl times/ 88 ch) transmission over 600-km NZDSF with VIPA variable dispersion compensators

Summary form only given. We performed 3.5-Tbit/s (43-Gbit/s /spl times/ 88 ch) 600 km transmission in the C- and L-bands by using virtually imaged phased array (VIPA) variable dispersion compensators. An adequate OSNR, which was the same for all the channels, was obtained by using distributed Raman amplification (DRA), a gain equalizer (GEQ), and a pre-emphasis technique. VIPA variable dispersion compensators can thus effectively overcome the small dispersion tolerance and temporal dispersion changes of dense WDM terabit systems. We achieved a Q-factor of more than 11.8 dB (BER < 10/sup -17/ with FEC) for all 88 channels.

40-Gbit/s transmission over high-PMD fiber with automatic PMD compensation

We achieved 40-Gb/s transmission over high-PMD fiber (/spl sigma//sub PMD/=9.7 ps) with automatic polarization-mode dispersion (PMD) compensation. We adopted a PMD monitor using the 20-GHz intensity of the received baseband signals and feedback control of an optical PMD compensator.

Optical Modulation and Dispersion Compensation Techniques for Ultra-High-Capacity TDM/WDM Transmission Systems

To realize ultra-high-capacity optical transmission systems, the combination of faster TDM and denser WDM is essential, and it is important to select an optical modulation scheme suitable to fiber type, transmission distance, and total capacity. We compared the dispersion tolerance at 40 Gbit/s for the optical duobinary, NRZ, and RZ modulation schemes. In transmission systems with a relatively small fiber launched power where the SPM GVD effect is small, the optical duobinary scheme with large dispersion tolerance has a significant advantage. On the other hand, in a transmission system with large SPM-GVD effect, precise dispersion compensation is essential for any optical modulation scheme. Using strict dispersion compensation at every in-line repeater for each channel and out-band FEC, 40 Gbit/s×16 channel (200 GHz spacing) NRZ signals can be transmitted over 600 km NZ-DSF. We introduced our 40 Gbit/s automatic dispersion compensation experiment using a tunable laser and discussed dispersion slope compensation.