Wavelength division multiplexing in long-haul transmission networks

Wavelength division multiplexing shows great promise for the next generation of undersea optical cable networks. WDM techniques will allow for greater transmission capacity and network flexibility compared to the present single-channel optical amplifier systems. This paper describes techniques used to transmit many WDM channels over transoceanic distances using the non-return-to-zero format and other non-soliton methods. Data is presented for several WDM experiments including the transmission of 100 Gb/s (twenty channels of 5 Gb/s) over 9100 km.