Experimental Studies on Four Channel Repeaterless WDM Transmission Using Semiconductor Optical Amplifiers in 1.3-μm Wavelength Band

Abstract

Application of semiconductor optical amplifiers to a 2.5Gbit/s×4 WDM repeaterless transmission system using the 1.3-μm wavelength band has been studied. Measured gain characteristics and bit error rate properties for 2.5Gbit/s signals amplified by the SOA's are found to be enough for post and pre-amplifier of the 4-channel WDM. The repeaterless transmission experiment over a 100-km SMF shows the allowable line loss of 32.8dB, and the same results are obtained by a experiment using fibers constructed in the field. Problems of applying SOA's to the WDM system such as its stability degradation due to polarization fluctuation and the influence of interference among channels are studied. When suitable margin is considered in the system, the influence of a polarization fluctuation is negligible. However, in order to avoid interference among channels, input optical power of the SOA should be around -22dBm/ch for 4-channel WDM.