Erbium doped fiber amplifiers-a new design tool that will rewrite transmission rules

Coupled with the low fiber loss at 1550 nm, erbium-doped fiber amplifiers (EDFAs) offer system performance not previously attainable. The designer is introduced to the limits that attenuation and dispersion place on single-hop system designs. A distributed feedback (DFB) laser spectral width of 1 nm (including chirp) is assumed throughout the examples of digital systems transmitting at 2.4 gigabits per second (Gbps). External modulation may be used to reduce source spectral width and extend the results presented. An optically amplified system schematic diagram is presented. The examples include calculations for maximum span length using a single optical amplifier and maximum route length for amplifiers in cascade.