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Prof. Roberto Gaudino, through ISMB, was the coordinator of the EU FP6 IST
project called "POF-ALL" (here is the
project web-site) and is now the
coordinator on the new project "POF-PLUS" in EU FP7 IST. The framework of
the new project can be found in the
POF-PLUS web site.
Shortly, POF-PLUS
will study during its three years duration (2007-2009) the application of
plastic optical fiber to very high speed domotic network. In particular, we
will study gigabit and multi-gigabit per second transmission over thick and
resilient plastic optical fibers.
An overview of the
achievements we obtained in POF-ALL can be found
in this paper.
Some general
information on POF
Plastic Optical Fibers (POF) are today considered a sound option for
wireline very high speed data transmission over distances in the range
from a few to 200 meters, that is for typical Local Area Networks
connections, for intra-vehicle links, and for Very Short Reach (VSR)
interconnections. The use of POF is interesting for all applications where
traditional solutions, such as copper wires or Glass Optical Fibers (GOF)
are inadequate or too expensive. In the last years we see a rising
international interest towards POF, as testified by an ample literature (see
[1-19] and [chem1-chem9]), and
by the increasing number of companies, even of remarkable size, who become
involved in plastic fibers and related devices [2-6].
In terms of distance and transmission speed (bit rate), the performance
of POF are potentially higher than what feasible with the best copper
cables, while costs are significantly lower compared with a GOF system.
Current (bitrate*distance) figure is about 100 Mbps for 100 meters for
standard POFs [8], and over 1 Gbps across 1 km for
advanced POF, with graded index (GI-POF [1,7]). Such
performance is well above copper cabling, and open new application areas [9],
as discussed later. Glass fibers giver higher performances, but with far
higher cost. The manufacturing cost for POF is today comparable with that
for multimodal GOF, but shows ample margins for improvements in case of
mass production. Most of the actual savings of POF are related with
installation costs. Namely, thanks to the wider cross section (15 times
the GOF, that is 1 mm vs. 62,5 micron), installation and maintenance of a
POF network can be carried out by technicians without specific tools and
related training. A cutter and a piece of small grain grinding paper are
the only tools needed to mount connectors. The current estimation is that
a complete termination can be carried out in approx. 30 minutes.
A specific characteristic of fiber interconnection is the total
insensitivity to electromagnetic interference (EMI). They are not subject
to noise and interference from radio transmitters or other electrical
appliances, and this increases the link reliability. For the same reasons,
fibers do not radiate electric or magnetic fields, therefore they are free
of health risk and do not contribute to electromagnetic environmental
pollution. These characteristics show advantages over copper cables, which
often require heavy and expensive shielding for use in
electro-magnetically noisy environment.
Moreover, the use of a polymeric material instead of silica, and their
wide diameter, give to POF (with respect to GOF) higher mechanical
strength and the ability to withstand strong shocks and vibrations.
Plastic fiber is tolerant to elongation, bending (the minimum curvature
radius is only 20 mm), and torque. Thanks to these features, in most
installation the wide, heavy and costly external coating needed for a GOF
is not required. The weight of a standard POF is about 6 g/m,
corresponding to one third of a GOF and one fourth of a UTP class 5 cable.
The total diameter is only 2,2 mm; this feature and their very high
flexibility make possible to route a GOF even through very narrow ducts.
Preliminary analysis estimate that the environmental impact for
manufacturing is lower for POF than for copper or GOF; this argument is
gaining high consideration for any industrial production, and contributes
to lower the total lifecycle cost of a POF system.
As a carrier of light but not of electricity, the plastic fiber
guarantees near perfect galvanic isolation. Its use is profitable whenever
the systems to be connected have different potential, such as in power
generation plants, when driving high power electronics, or in high-safety
devices. For the same reason a fiber is intrinsically more safe than an
insulated electric cable in case of risks related with electrical fields
(e.g. with exploding gases or powder).
Fibers are typically used with visible-light and low power optical
sources, and that makes possible to verify the connection continuity and
fault location with a simple no-risk visual inspection. This is not
possible with copper cables and GOF; these last use high power infrared
light sources (Lasers), which are potentially very dangerous for the human
eye.
All these characteristics make very interesting in the medium term the
introduction of POFs in the following application areas:
- Industrial cabling [10]: as an alternative
solution for traditional copper cabling, with great benefits expecially
for the tolerance to electromagnetic interferences and the intrinsic
galvanic isolation between transmitter and receiver (since ground loops
are totally avoided).
- Domotic applications [9]: several companies
[2-6] are evaluating POF as transmission media for
links within home networks, especially for high-end entertainment systems
(interactive high definition video). A first step in this direction is the
publication of the new High-Definition Multimedia Interface (HDMI)
standard [12], for the interconnection at very high
bit rate of high definition TV (bit rate up to 5 Gbps).
- Local Area Networks: as an alternative to current copper
cabling, especially when the previously described features of POF can be
useful.
- Automotive applications: current high-end cars, and the future
drive-by-wire vehicles need a "data network" inside the vehicle,
with high bandwidth and reliability. Several manufacturers are evaluating
the use of POF, as testified by the MOST consortium [13],
which gathers the main European car manufactures. In this context, the POF
bring benefits towards copper cabling for the high immunity to
electromagnetic disturbances and for the lower weight. Similar
consideration apply to avionic applications [14].
- Other "niche" applications, difficult to evaluate
beforehand, where the specific characteristics of POF can bring benefits.
This applies for instance to any type of interconnection in hostile
environment, or with specific safety needs (e.g. medical and life-support
equipment).
- The last example deals with two application areas, not
addressed in this project, which have raised strong interest: the use of
POF as sensing devices and for illuminating engineering (by the way,
illumination is the first area of application for which POF were invented
and built)
After these remarks on potential applications, we must specify that the
commercial use of POF is still in his infancy, mainly for the following
reasons:
- Very poor knowledge of POF features, almost unknown in several
areas. - Poor availability of complete POF transmission systems, balanced
however by the increasing number of discrete devices for POF [2-6],
which testifies that several companies bet on the future developments in
this field.
- Lack of complete demonstration testbeds, with a few exceptions
in Japan [9] and Korea [15].
- Some negative technical features of POF, such as poor behavior
at high temperatures (a critical issue for automotive and avionic
applications), and high attenuation and dispersion. Improvements of these
parameters can be achieved only through basic research in the field of
polymeric materials, as indicated in the set of international references [chem1-chem9].
For these reason it is quite obvious to find several international
research centers active in the field; more in detail: - Most activities
are carried out in Japan, within or in connection to the most important
(on a worldwide basis) research center, co-ordinated by Prof. Koike at the
University of Tokio [1], and some companies such as
Asashi Glass [2] and Mitsubishi [3].
In Japan [9] (as well as in Korea [15]),
thanks to huge investments of the government, a few residential campuses
are completely connected by POF, to demonstrate the real feasibility of
this technology. - In Europe the most important centers are the POF
Application center (POF-AC, [7]), involved in many
research projects, the EITT consortium [16], and the
Basque University in Spain [17]. The companies most
active in POF applications are Nexans [4], mainly for
industrial cabling, Firecomms [5] and Infineon for the
development of optical POF components. - In U.S., besides the large
consortium POF Trade Organization (POF-TO [18]),
several big companies such as Agilent and Digital Optronics.are involved
in the development of POF devices.
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Introductory references on POF:
[1] T. Ishigure, Y. Koike, "Design of POF for
Gigabit Transmission", POF Conf. 2003, pp. 2-5, Seattle, Sept
2003
[2] Asashi Glass Co, Ltd., web site: www.agc.co.jp/english/index.html
[3] Mitsubishi Rayon Co., Ltd., web site: www.mrc.co.jp/english
[4] Nexans Co., web site: www.nexans.com
[5] Firecomms Co., web site: www.firecomms.com
[6] Luceat SpA, web site: www.luceat.it
[7] O. Ziemann, J. Vinogradoc, E. Bluoss, "Gigabit
per second data transmission over short POF links", POF Conf. 2003,
pp. 20-23, Seattle, Sept 2003
[8] H.P.A. van den Boom, W. Li, P.K. van Bennekom,
I.T. Monroy, Giok-Djan Khoe, "High-capacity transmission over polymer
optical fiber", IEEE J. Select. Topics in Quantum Electron., Vol. 7 ,
pp. 461-470, 2001
[9] Yamazaki, S.; Shikada, M., "POF for
high-speed PC and home networks", Optical Fiber Communication Conf.
and Exhibit OFC '98., Technical Digest, 22-27 Feb. 1998 Pages:307
[10] R. Beach, "Enabling next generation
control networks with plastic optical fiber solutions", POF Conf.
2003, pp. 20-23, Seattle, Sept 2003
[11] IEEE 1394 (Firewire) protocol,www.1394ta.org/Technology/index.htm
[12] High Definition Multimedia Interface, www.hdmi.org
[13] MOST Cooperation, www.mostnet.de
[14] EU FP5 project: "MOTIFIES: Multimedia
Optical-Plastic Technologies for In-Flight Entertainment", www.nmrc.ie/projects/motifes
[15] J.W. Lee, "Realization of FTTH for the
integration of telecommunication and broadcasting", POF Conf. 2003,
pp. 20-23, Seattle, Sept 2003.
[16] European Institute of Telecommunications
Technology (EITT), web site: www.eitt.dk
[17] G. Durana, J. Zubia, J. Arrue, "Study of
polarization in plastic optical fibers", POF Conf. 2003, pp. 20-23,
Seattle, Sept 2003.
[18] POF Trade Organization (POF-TO), web site: www.pofto.com
[19] C. Boulet, D. J. Webb, M. Douay, P. Niay,
" Simultaneous interrogation of fiber Bragg grating sensors using an
acoustooptic tunable filter", IEEE Photonic Tech. Letter, Vol. 13,
no. 11, 2001.
[20] Fastweb, web site: www.fastweb.it
[21] Luciol Instruments, Ltd, web site:
www.luciol.com [22] ST Microelectronics, web site: www.st.com
International papers dealing with polymers and materials for POF.
[chem1] Y. Koike, Y. Takezawa, Y. Ohtsuka, Appl.
Opt. 1988, 27, 486
[chem2] J. Zubia, J. Arrue, Opt. Fiber Tech.
2001, 7, 101
[chem3] J. Masere, L.L. Lewis, J.A. Pojman, J.
POlym. Sci. Polym Sci. 2001, 80, 686
[chem4] T. Ishigure, M. Sato, A. Kondo, Y. Koike,
J. Lightwave Technol. 20 (2002) 1443-1448
[chem5] M. Zhou, Optical Engineering 41 (2002),
1631-1643
[chem6] K. Kuriki, Y. Koike, Y. Okamoto, Chem.
Rev. 102 (2002) 2347-2356
[chem7] Li, G.Z.; Wang, L.; Toghiani, H.; Daulton,
T.L.; Pittman Jr, C.U.; "Viscoelastic and mechanical properties of
vinyl ester (VE)/multifunctional polyhedral oligomeric silsesquioxane (POSS)
nanocomposites and multifunctional POSS-styrene copolymers" Polymer,
2002, 43 (15), pp. 4167-4176
[chem8] Alexandre, M.; Dubois, P., "Polymer-layered
silicate nanocomposites: preparation, properties and uses of a new class
of materials", Materials Science and Engineering: R: Reports Vol: 28,
Issue: 1 -2, 2000 pp. 1-63
[chem9] Marigo, A., Marega, C., Zannetti, R.,
Sgarzi, P., "A study of the lamellar thickness distribution in
1-butene, 4-methyl-1-pentene and 1-hexene LLDPE by small and wide angle
X-ray scattering and transmission electron microscopy", Authors
European Polymer Journal, 1998, 34(5-6), pp. 597-603 |
