Integrated optic devices for coherent transmission

The components required for coherent optical-fiber systems are discussed and those devices that can be implemented using electrooptic waveguide technology are identified. The current usage of integrated optic components in coherent optical-fiber systems is indicated and the system performance that has been obtained when these components are employed summarized. The design and performance of LiNbO 3 electrooptic waveguide modulators, optical combiners, frequency translators, and polarization controllers are reviewed and the benefits to be gained by employing optical-integrated circuits in coherent optical-fiber systems considered. Finally, a novel low-voltage LiNbO 3 optical-integrated circuit for use in coherent detection is presented and the various design compromises discussed.