OPTICALLY-AMPLIFIED WDM RING NETWORK INCORPORATING CHANNEL-DROPPING FILTERS

We analyze the critical parameters in an optically-amplified WDM ring network. We find that a ring can accomodate 27 nodes when incorporatin g an EDFA and a channel-dropping filter in each node, a significant ad vance over nonamplified rings. We compare several node configurations, and find that the sequence of an EDFA followed by an optical tap and a channel dropping filter provides the highest performance for a wide range in system variables including input signal power, inter-node lin k loss and its variability, power-tapping ratio, and small-signal gain . Limited network modularity can be achieved.