BRIGHT PROSPECTS FOR ERBIUM-DOPED FIBER AMPLIFIERS IN FUTURE LIGHTWAVE COMMUNICATION-SYSTEMS

In the light of achievable component performance from both a theoretical and an experimental point of view, the applications of erbium-doped fiber amplifiers (EDFA) in long distance repeaterless digital transmission and analog cable TV distribution is discussed. In digital repeaterless systems, EDFA postamplifiers are capable of output powers over + 15 dBm; preamplifiers and remotely pumped amplifiers improve system budgets by more than 7 dB and 13 dB, respectively, when compared to a conventional APD (avalanche photodiode) receiver. In analog AM-VSB TV distribution networks, EDFA postamplifiers improve the power budget by more than 10 dB, and cascaded EDFA repeaters hold promise for power budgets over 35 dB, allowing large splitting ratios in the network.