IP: MPT Japan STAR Project Summary Outline

[David Farber <farber () cis upenn edu>]

                                  STAR
        (Soliton-based Total All-optical communication-network Research)






INTRODUCTION


        In July 1996, the Japanese government established the Science and
Technology Basic Action Programs through which government can spend its money
more effectively to prepare Japan as a leading science and technology
nation of
the 21st Century.


        The main areas of implementation include (1) expansion of governement's
research and development investment; (2) construction of innovative research
and development systems; and (3) promotion of collaborative work among
industry, academia and government.  For these purposes, the national budget
for
technology will increase yearly up to $3.8 Billion, or 1% of GNP, in the year
2000. 
        
        The STAR Project has been selected as one of the strategically
important national research and development projects sponsored by the Japanese
Ministry of Posts and Telecommunications.  It is expected to contribute
greatly
in upgrading the current one to the next generation network infrastructure
using ulta high-speed optical network technologies.




MAIN OBJECTIVES


        The STAR Project aims at constructing terabit per second all-optical
networks over global distances based on the optical soliton concept, in order
to meet the subscriber's acute demand for multimegabit multimedia services
which are expected in the early 21st Century.  The Project has its basis in
matching the expected social demand on the technical feasibility required to
respond to the demand.




SPONSOR & PARTICIPANTS


        The STAR Project is financially supported by the Japanese Ministry of
Posts and Telecommunications as one of the national projects in the promotion
of science and technology.  It was started in 1996 and is expected to continue
for ten years.  The Project is administered by a Planning Committee
established
within the Support Center for Advanced Telecommunications Technology Research
Foundation (SCAT).  The members of the committee consist of Professor Akira
Hasegawa, the Chair, Professors Kazuro Kikuchi and Tetsuya Miki, Drs. Kiyoshi
Nosu and Kazuo Sakai, and Mr. Takayuki Wada, Secretariat.  The participating
organizations as of 1996 are, in alphabetical order, Fujikura, Fujitau,
Mitsubishi Electric, NEC, Oki, Sumitomo Electric and Toshiba.  Osaka
Unviersity
and The University of Electro-Communications are schjeduled to jion in 1997.




TECHNICAL APPROACH


        A terabit per second global network requires a factor of a hundred
enhancement in the product of transmission speed and distance (bit-distance
product) over the presently available systems.  Such an enhancement may be
achieved by a combination of wavelength multiplexing (WDM) and optical time
division multiplexing (OTDM) within the gain bandwidth of an Erbium Doped
Fiber
Amplifier (EDFA), assisted by opitcal signal processing and switching as well
as properly programmed fiber dispersion.  A feasible combination of OTDM and
WDM will be 100 GB/s transmission rate per channel with 10 wavelength
channels.


        All optical processing is most easily achieved by the use of Return to
Zero (RZ) pulses having distance-independent pulse shapes with a reasonable
energy per pulse.  Solitons satisfy these requirements in addition to their
ability to render the maximal bit-distance product per wavelength channel.
However, in order to achive the 100 GB/s transimission rate over a global
distance, solutions to intrinsic problems of solitons, such as the requirement
of peak power proporational to the bit rate squared, inefficient use of
bandwidth due to the requirement of large separation between adjacent pulses,
and time jitters induced by amplifier noise, should be solved.  We believe
that
these problems can be solved with proper dispersion management and careful
preparation of the initial pulse shape.


        In addition to the transmission issue, we need to develop proper
technologies for the light source, signal processing and switching, adaptable
to a terabit per second WDM-TDM combined systems.


        The consortium is responsible for the development of the compact light
source, mux and demux devices, EDFA with flat gain characteristic, low loss
fiber with desired dispersion profiles, and all optical add/drop/switching
devices.  It is also expected to provide leadership in theoretical and
computational support for the entire project.




KEY ISSUES


        Development of a new soliton which requires less peak power and weaker
interactions.


        Development of WDM/OTDM terabit light source and all-optical signal
processing.


        Development of all-optical add/drop switching.


        Development of low noise EDFA with a flat gain profile.


        Development of low loss fiber with a programmed dispersion profile.






EXPECTED IMPACTS


        Successful development of global terabit systems will allow world wide
subscribers global multimedia access to multimegabit/s networks.  This will
bring about a truly new era for multimedia networks in which telephones are
replaced by personal computers.


        Optical components for signal processing and switching to be developed
simultaneously in this project also opens a new era in optoelectronics in
which
a transition from electronics to optics takes place in analogy to the
transition from electromechanical systems to electronics in the 1950s.  It
will
produce a significant impact on ultra high speed data processing in the next
generation of computers.