Present and future undersea transmission systems

Undersea lightwave transmission systems have experienced an explosive evolution since their first application as transoceanic systems in 1988. The paper reviews the various aspects of this evolution. Starting with the evolution from simple lightwave transmission systems that provided point-to-point connectivity to sophisticated undersea communication networks that added highly desirable advanced features such as path selective branching on network restoration capability, and fast restoration capability for priority traffic. The underlying transmission technology that has enabled this evolution has grown from 280 Mbit/s per fiber pair for the first generation transmission systems to today´s systems implemented with optically amplified transmission technology operating at 5 Gbit/s per fiber pair. The prognosis is for 100 Gbit/s transmission capability in the not too distant future, employing wavelength-division multiplexing over optically amplified transmission systems. The paper reviews technological advances and provides an outlook for future evolution. Third, the paper examines new undersea branching technologies, which will allow sophisticated undersea networks to be constructed with future capabilities for restoration and reconfiguration. The paper examines these major evolutionary trends for undersea lightwave technology and provides an outlook for the future