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Chapter 1: Overview
Ivan P. Kaminow
AT&T Bell Laboratories (retired), Holmdel, New Jersey
History
Optical Fiber Telecommunications, edited by Stewart E. Miller and Alan G. Chynoweth, was published in 1979, at the dawn of the revolution in lightwave telecommunications. This book was a stand-alone volume that collected all available information for designing a lightwave system. Miller was Director of the Lightwave Systems Research Laboratory and, together with Rudi Kompfner, the Associate Executive Director, provided much of the leadership at the Crawford Hill Laboratory of Bell Laboratories; Chynoweth was an Executive Director in the Murray Hill Laboratory, leading the optical component development. Many research and development (R&D) groups were active at other laboratories in the United States, Europe, and Japan. The book, however, was written exclusively by Bell Laboratories authors, although it incorporated the global results.
Looking back at that volume, I find it interesting that the topics are quite basic but in some ways dated. The largest group of chapters covers the theory, materials, measurement techniques, and properties of fibers and cables - for the most part, multimode fibers. A single chapter covers optical sources, mainly multimode AlGaAs lasers operating in the 800- to 900-nm band. The remaining chapters cover direct and external modulation techniques, photodetectors and receiver design, and system design and applications. Still, the basic elements for the present-day systems are there: low-loss vapor-phase silica fiber and double-heterostructure lasers.
Although a few system trials took place beginning in 1979, it required several yearsbefore a commercially attractive lightwave telecommunications system was installed in the United States. This was the AT&T Northeast Corridor System operating between New York and Washington, DC, that began service in January 1983, operating at a wavelength of 820 nn and a bit rate of 45 Mb/s in multimode fiber. Lightwave systems were upgraded in 1984 to 1310 nm and about 500 Mb/s in single-mode fiber in the United States, as well as in Europe and Japan.
Tremendous progress was made during the next few years, and the choice of lightwave over copper for all long-haul systems was ensured. The drive was to improve performance, such as bit rate and repeater spacing, and to find other applications. A completely new book, Optical Fiber Telecommunications 11 (OFT ll), edited by Stewart E. Miller and me, was published in 1988 to summarize the lightwave design information known at the time. To broaden the coverage, we included some non-Bell Laboratories authors, including several authors from Bellcore, which had been divested from Bell Laboratories in 1984 as a result of the court-imposed "Modified Final Judgment." Corning, Nippon Electric Corporation, and several universities were represented among the contributors. Although research results are described in OFT ll, the emphasis is much stronger on commercial applications than in the previous volume.
The early chapters of OFT II cover fibers, cables, and connectors, dealing with both singleand multimode fiber. Topics include vapor-phase methods for fabricating low-loss fiber operating at 1310 and 1550 nm, understanding chromatic dispersion and various nonlinear effects, and designing polarization-maintaining fiber. Another large group of chapters deals with a wide geographic scope of systems for loop, intercity, interoffice, and undersea applications. A research-oriented chapter deals with coherent systems and another with possible local area network applications, including a comparison of time-division multiplexing (TDM) and wavelength-division multiplexing (WDM) to effectively utilize the fiber bandwidth. Several chapters cover practical subsystem components, such as receivers and transmitters, and their reliability. Other chapters cover the photonic devices, such as lasers, photodiodes, modulators, and integrated electronic and integrated optic circuits, that compose the subsystems. In particular, epitaxial growth methods for InGaAsP materials suitable for 1310- and 1550-nm applications, and the design of high-speed single-mode lasers are discussed.
The New Volume
By 1995, it was clear that the time for a new volume to address the recent research advances and the maturing of lightwave systems had arrived. The contrast with the research and business climates of 1979 was dramatic. System experiments of extreme sophistication were being performed by building on the commercial and research components funded for a proven multibillion-dollar global industry. For example, 10,000 km of highperformance fiber was assembled in several laboratories around the world for NRZ (non-return-to-zero), soliton, and WDM system experiments. The competition in both the service and hardware ends of the telecommunications business was stimulated by worldwide regulatory relief. The success in the long-haul market and the availability of relatively inexpensive components led to a wider quest for other lightwave applications in cable television and local access network markets. The development of the diode-pumped erbium-doped fiber amplifier (EDFA) played a crucial role in enhancing the feasibility and performance of long-distance and WDM applications.
In planning the new volume, Tom Koch and I looked for authors to update the topics of the previous volumes, such as fibers, cables, and laser sources. But a much larger list of topics contained fields not previously included, such as SONET (synchronous optical network) standards, EDFAs, fiber nonlinearities, solitons, and passive optical networks (PONS). Throughout the volume, erbium amplifiers, WDM, and associated components are common themes.
Again, most of the authors come from Bell Laboratories and Bellcore, where much of the research and development was concentrated and where we knew many potential authors. Still, we attempted to find a few authors from elsewhere for balance. Soon after laying out the table of contents and lining up the authors, however, a bombshell and a few hand grenades struck. AT&T decided to split into three independent companies, Bellcore was put up for sale, and several authors changed jobs, including Tom Koch and I. The resulting turmoil and uncertainty made the job of getting the chapters completed tougher than for the earlier volumes, which enjoyed a climate of relative tranquillity.
In the end, we assembled a complete set of chapters for Optical Fiber Telecommunications 111, and can offer another timely and definitive survey of the field. Because of the large number of pages, the publisher recommended separating the volume into two sections, A and B. This format should prove more manageable and convenient for the reader. The chapters are numbered from Chapter 1 in each section, with this Overview repeated as Chapter 1 in both sections A and B to accommodate users who choose to buy just one book.
Survey of Volumes IIIA and IIIB
The chapters of Volumes IIIA and IIIB are briefly surveyed as follows in an attempt to put the elements of the book in context...
