@article{RodesLópez:7592,
author = "Rodes López, Guillermo Arturo and Otín Acín, Aránzazu",
title = "{Optical switching for dynamic distribution of
wireless-over-fiber signals in active optical networks}",
year = "2012",
note = "The ever growing demand of bandwidth by end users has put
a lot of pressure on access networks. Access networks,
mainly employing wireless technologies, are turning to
optics to support such large bandwidth requirements.
Depending on the requirements and features of the end
users, optical access networks have evolved in different
directions. In residential and urban environments, users
demand fix connections with high capacity at low price.
Passive optical networks (PON) have fulfilled these
requirements and are the operators chosen technology. In
business environments, in which quality assurance and
security are key issues, active optical networks (AON) have
found their niche, providing flexibility, adaptability and
high throughput while supporting tight management systems.
Vendors are now turning their eye to new markets where
optics can be used effectively. Mobile backhaul is a target
market, since mobile traffic is growing exponentially –
new gadgets along with killing applications are fueling
such growth. Baseband technologies can support mobile
backhaul effectively at current rates. However, due to the
location of new license-free available frequency bands and
the development of radio-over-fiber (RoF) technologies –
allowing generation, distribution and reception of micro-
and millimeter wave band signals optically, migration
towards wireless-over-fiber scenarios are likely.
Furthermore, concerns on security and high mobility seem to
indicate active solutions may be in favor of system
designers, provided that cost and energy consumption are
maintained within reasonable limits. In this thesis, an
optical access network based on radio-over-fiber
technologies was designed. An active optical switch based
on active components (semiconductors optical amplifiers
(SOAs)) was used as main building block; the rest of the
network was designed according to the channel distribution
over the optical spectra required by the optical switch. An
experimental validation was conducted. The experiment
consisted in the implementation of a four channel system
operating on a worldwide interoperability for microwave
access (WiMax) frequency band, and employing an orthogonal
frequency-division multiplexing (OFDM) modulation at 625
Mbit/s per channel, transmission of the data over 20 km of
optical fiber, and active switching in a one-by-sixteen
active optical switch. The results show a negligible power
penalty on each channel, for both the best and the worst
case in terms of inter-channel crosstalk. The system meets
the requirements for an AON for wireless-over-fiber for
optical access networks (OAN).",
}