Equalization Advantages of OFFH-CDMA over WDM in EDFAs

This study stems from the observation that 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 OFFH-CDMA (optical
fast frequency hopped code division multiple access)
offers a natural diversity of wavelength, thus
eliminating the requirement of an equalization stage
to achieve flat gain on all channels. In this work,
computer simulations are developed to analyze
equalization performance of these two transmission
approaches (CDM and WDM) in EDFAs, especially when
the EDFA operating point is subject to change (i.e.,
variable input traffic). The simulations are based on
extensive modeling of WDM and OFFH-CDMA network
architectures and signals, self-similar traffic, and
EDFAs. The required background is presented in three
strong tutorial chapters. This study should be useful
to anyone working in the area of optical
communications, particularly to students and research
professionals. The conclusions may be greatly
relevant to the development of future
packet-over-light access and metropolitan networks
over the next decades.