Optical amplifiers and wavelength-multiplexing technology are transforming lightwave communications by providing cost-effective upgrades that will increase immensely the transmission capacity of long-distance telecommunications networks. A new generation of undersea cable systems using fiber optical amplifiers as repeaters has been developed for transoceanic applications, yielding a capacity almost ten times larger than conventional systems using opto-electronic regenerators. Terrestrial long-haul networks will benefit significantly from amplified wavelength-multiplexed transmission systems designed to access the large inherent bandwidth in the installed fiber. Successful deployment of these advanced systems requires a thorough understanding of optical amplifiers and the optical fiber medium, as their requirements interrelate through optical bandwidth, noise, dispersion, optical nonlinearities, and their impact on signal transmission. While the first commercial WDM amplified lightwave systems are deployed for point-to-point applications, optical transparency and wavelength multiplexing will be exploited for networking leading to the higher functionality and improved cost-effectiveness expected of photonic networks.

The potential of erbium-doped fiber amplifiers (EDFA) and wavelength-division multiplexing (WDM) technology for expanding transmission capacity in long-distance telecommunications is examined. Properties of EDFA are nearly ideal for application in lightwave long-haul transmission. Nonlinear effects in the transmission fiber and amplifier spontaneous emission noise limit the performance and therefore dictate the design of long-distance amplified systems, especially those employing WDM. The next-generation transoceanic system will use EDFA as repeaters, yielding a capacity almost ten times larger than what is available today. Multichannel WDM soliton transmission promises further substantial enhancement. Terrestrial long-haul networks will also benefit greatly from amplified WDM systems designed to mine the large inherent bandwidth in the embedded fiber. The ten- to fifty-fold capacity increase over present systems not only will provide for ample growth, but also will enable network operators to enhance operational flexibility and network functionality, and to facilitate a fast-recovery self-healing capability through cost-effective redundant routing.>

Following a decade of intensive research, optical fiber transmission emerged in the late 1970's as a major innovation in telecommunications. This paper reviews the progress in the field of optical fiber communication. Advances in the areas of fibers, cables, passive components, active devices, and systems are presented in historical perspective. Recent research and development accomplishments that are likely to have important impact on future systems are emphasized.

Optical-fiber transmission lines appear attractive for a variety of communication applications in which twisted copper pairs and coaxial cables are now used. These applications range from onpremises data links and equipment wiring to interoffice and intercity telecommunications trunks. Experiments to explore the technical feasibility of glass fibers in these areas are presently in progress. This paper summarizes the state of the art of the burgeoning field of optical fibers. Progress in research on fibers, cables, devices, and components will be reviewed, and systems applications and field experiments will be discussed.

Optical-fiber transmission lines appear attractive for a variety of communication applications in which twisted copper pairs and coaxial cables are now used. These applications range from on-premises data links and equipment wiring to interoffice and intercity telecommunications trunks. Experiments to explore the technical feasibility of glass fibers in these areas are presently in progress. This talk summarizes the current state of research on optical fibers, fiberguide cables and splicing techniques, reviews the state of the art of fiber-compatible sources and detectors, and discusses various systems considerations, experiments and applications.