AM Lightwave Technology

The rapid evolution of lightwave transmission systems, from the early 45-megabit-per-second FT-3 to the present 2.4-gigabit-per-second FT-2000, took place during a period in which telephone networks have added only digital capacity. As a result, the primary applications for lightwave transmission technology, and the infrastructure required to support it, have been almost entirely digital. The applicability of available lightwave technology to CATV systems is not obvious. In this paper, we compare broadband analog systems to available digital technology, focusing on critical parameters for each application. We report on the significant improvements in electronic and media components that are part of a working AM broadband system, and on the architectural flexibilities that result from having broadband analog as well as high-speed digital facilities available for future lightwave system architectures.