Raman Amplifier with Integrated Dispersion-Compensating Fiber

It has been more than 20 years since fiber-optic communication became practicable, and there has been a continuing stream of technological breakthroughs. The increased diffusion of the Internet has seen the rapid introduction of dense wavelength division multiplexing (DWDM) systems. With the burgeoning increases in communications capacity in recent years 1), attention has been focused on Raman amplifiers 2), 3), and work goes forward on applying them to various systems. During the 1980s much work was done on the technology of Raman amplification as a prime contender for use as a fiberoptic communications amplifier, but at the practical level the development and adoption of the erbium-doped fiber amplifier meant that this never went beyond the research stage. However as bit rates progressed from 2.5 Gbps to 10 and even 40 Gbps, it became difficult to design systems with only EDFAs, and the advantages of distributed Raman amplification, in which the transmission path itself serves as the amplification medium, were recognized. More recently, the use of Raman amplification while optimizing the dispersion characteristics of the transmission path has become an indispensable technology for upgrading transmission capacity and transmission limits. That is to say in order to upgrade transmission capacity, technologies for optimizing Raman Amplifier with Integrated Dispersion-Compensating Fiber