Patent ID: 7292790

Claim:
An optical communication network comprising: a plurality of transmission fiber links in optical communication with each other; a plurality of amplifiers in optical communication with said transmission fiber links; a first type of dispersion compensating fiber in optical communication with said transmission fiber links, said first type of dispersion compensating fiber providing a first residual dispersion having a residual dispersion versus wavelength profile having an Nth order term and a Nth order coefficient, N being greater than 1; a second type of dispersion compensating fiber in optical communication with said transmission fiber links and said first type of dispersion compensating fiber; a combination of said first type of dispersion compensating fiber and said second type of dispersion compensating fiber providing an effective residual dispersion having an effective residual dispersion versus wavelength profile with an effective Nth order coefficient that is less than the Nth order coefficient; wherein: said first type of dispersion compensating fiber has a dispersion characteristic represented in part as: D DCF2 =a 2*λ+ b 2*λ N , and said second type of dispersion compensating fiber has a dispersion characteristic 5 represented in part as: D DCF3 =a 3*λ+ b 3*λ N , said effective Nth order coefficient being equal to: αb2+(1−α)b3, where α represents a proportion of said first type of dispersion compensating fiber to a total amount of said first type of dispersion compensating fiber and said second type of dispersion compensating fiber.