Equalization Advantages of OFFH-CDMA over WDM in EDFAs

摘要

The gain of an EDFA (erbium doped fiber amplifier) is in general wavelength-dependent, leading to different amplification levels among WDM (Wavelength division multiplexing) channels. The use of Optical FFH-CDMA (fast frequency hopped code division multiple access) offers a natural diversity of wavelength, and therefore gain, thus eliminating the requirement of an equalization stage of achieve flat gain on all channels. Computer simulations are developed to analyze and compare equalization performance of these two transmission approaches (CDM and WDM) in EDFAs, especially in situations where the EDFA operating point is subject to change (i.e., variable input traffic). We find that WDM requires an equalization stage that fails when packetized traffic characteristics shift, whereas optical FFH-CDMA presents the advantage of mor erobust, hence truly dynamic, gain equalization.