Special Issue on Fiber Optics

E live in an age of rapidly evolving new technologies, one of which is optical fiber communication. As with microelectronics, the pace with which this technology has matured is so fast that to a large extent growth of commercial applications in the next few years will be regulated more by the ability of potential users and suppliers to understand and apply the technology, and to establish standards, than by the limitations of the technology itself. In a little over ten years, optical fiber communication has evolved from a research proposal to a commercial reality. Fiber losses have been reduced from 1 dB/m to 1 dB/km in the laboratory, and 5 dB/km in cables fabricated under production conditions. Room temperature CW injection lasers have been invented, and then their operating lifetimes extended from less then an hour to over one million hours. Practical cable structures and electronic subsystems have been designed. Finally, numerous experimental systems of varying sophistication have been installed in the field, some carrying live traffic. Applications have been proposed and/or implemented for telephone trunks, loops, short and long distance data links, video distribution, and more. Up to now, most journals featuring fiber optics have emphasized components (fibers, sources, detectors, etc.) and rightly so, as long as systems were in an early stage. Today, there is an proliferation of system experiments, economic studies and hardware appearing for sale. With this in mind, the Editors of the TRANSACTIONS ON COMMUNICATIONS proposed a Special Issue on Optical Fiber Systems. The Guest Editorial Committee has tried to present a broad picture of fiber systems applications. Contributions describing the various experimental installations were solicited from all known participants. The issue includes discussions of early fiber applications such as digital telephone trunks and point to point data links, as well as more speculative applications such as multiple access data buses, video networks and wavelength multiplexed systems. Also included are articles on the economics of fibers and analytical studies of receiver performance. In selecting analytical papers the Editors had to choose between those contributions which genuinely broke new ground, and those which merely provided more detailed analysis with no new concepts. Specifically the following unsolved analytical issues are at least partially addressed here: new analysis techniques which can be proven to be more accurate or 945