Novel 1470-nm-Band WDM Transmission and Its Application to Ultra-Wide-Band WDM Transmission

摘要

A novel 1470-nm-band (S+ band) wavelength-divi- sion multiplexing (WDM) transmission system is described. The first advantage of S~+-band transmission is suppression of degradation caused by four-wave mixing (FWM), which has been the dominant impair- ment factor in WDM transmission systems on dispersion-shifted fibers (DSFs). FWM suppression by using the S~+ band instead of the conven- tional 1550-nm-band (M band) is successfully demonstrated. The sec- ond advantage is expansion of the usable bandwidth by using the S~+ band together with other wavelength bands. A triple-wavelength-band WDM repeaterless transmission experiment using the S~+ band, the M band and the L band (1580-nm-band) is conducted over DSF, and it is shown that degradation due to inter-wavelength-band nonlinear inter- actions is negligible in the transmission. Moreover, the transmission performance of an S~+-band linear repeating system is estimated by com- puter simulation, and compared with that of other wavelength-band systems. In the experiments, thulium-doped fiber amplifiers (TDFAs) are used for amplification of signals in the S~+ band.