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Study on Electrical Power Distribution Among Coexisting OFDM-Based Wired-Wireless Signals Along Long-Reach Passive Optical Networks

Carvalho, F. ; Cartaxo, A.

Journal of Optical Communications and Networking Vol. 5, Nº 7, pp. 813 - 824, July, 2013.

ISSN (print):
ISSN (online):

Journal Impact Factor: 2,064 (in 2014)

Digital Object Identifier: 10.1364/JOCN.5.000813

The provision of a quintuple-play service
(fixed Internet and telephony, mobile telephony/Internet,
security/control applications, and wireless high-definition
audio/video distribution) along wavelength division multiplexing
long-reach passive optical networks has been
proposed recently. Five coexisting orthogonal frequency
division multiplexing based signals have been used to
deliver the quintuple-play service toeach user. In this paper,
the electrical power distribution (EPD) among those five
coexisting signals is studied using numerical simulation.
The need for EPD optimization is stressed, as the optimum
EPD(OEPD) enables the maximization of the signal and network
performances. The OEPD is achieved by setting optimized
gains (OG) in the electrical amplifiers used to impose
the electrical power level of each one of the coexisting signals.
For practicability, the gains are optimized only for a
specific fiber length.For other fiber lengths, the use of those
OG may cause performance degradation. This degradation
can be mitigated if a predistortion (PD) scheme, which compensates
for the frequency-dependent losses (FDLs) of the
transmission channel, is used with proper OG. It is shown
that the main advantage of using OG  PD over using OG
only is to enable the reduction of the performance degradation
that occurs for other fiber lengths than the one considered
in the OG optimization. The capability to mitigate
the FDLs is more limited in the absence of PD. Therefore,
the advantage of using OG  PD over OG increases with the
magnitude of the variation of the FDLs inside the band of
the signals. However, under the conditions considered in
this work, the impact of the use of OG  PD on the maximum
transmission reach (MTR) is determined to be reduced (less
than 1% relative to theMTRobtained withOGonly, 126.5km
of standard single-mode fiber).