Communications: ISDN services are introduced worldwide coherent optical communications components are developed in Japan fiber-optic submarine cable systems to span the Pacific additional spectrum space is allocated for mobile communications

The day when voice communications will be sent over the same lines as computer data and images moved closer in 1986 as some U.S. telephone companies held field trials of systems for an integrated-services digital network (ISDN). At the same time, several Japanese companies developed and tested components that promise to make coherent optical communication systems practical. And new spectrum space was opened in the United States for users of mobile communications.