Re: Marconi Communications Introduces 'Deep Fiber HFC' With RF Return Over Fiber-to-the-Curb
September 30, 1999
CHICAGO, Sept. 29 /PRNewswire/ via
NewsEdge Corporation -- Marconi
Communications (formerly RELTEC(R)
Corporation in the U.S.) today announced a
local loop access system that eliminates
many of the drawbacks of traditional hybrid
fiber coax (HFC) architectures and will enable
Multiple System Operators (MSOs) to offer
higher-quality Internet access and telephony
services to their cable television subscribers
while significantly reducing installation and
operating costs.
The "Deep Fiber HFC"(SM) system
incorporates a patented radio frequency (RF)
Return upstream capability into Marconi's
DISC*S(R) FiberStar(TM) flexible access
platform. The new capability enables a
service provider to deliver a variety of
high-bandwidth, high-reward services such
as high-speed Internet, impulse
pay-for-view, interactive gaming and
broadcast cable television, as well as lifeline
POTS (plain old telephone service) and other
narrowband services. The new architecture is
being initially trialed in a Southwestern U.S.
metropolitan area by one of the world's
largest MSOs.
"MSOs have been seeking a robust,
carrier-class, integrated video, data and
voice solution to respond to consumer
demand for new services while minimizing
installation and life-cycle costs," said Mike
Pratt, Marconi vice president and general
manager of the Access Network Systems
Group, Irving, TX. "Adding RF Return
capability to our proven DISC*S
fiber-to-the-curb platform enables cable
operators to run fiber very close to the home
and use the existing customer premise
equipment. Our 'Deep Fiber HFC' solution
offers advantages in the areas of power,
reliability, maintenance, scalability and
network evolution."
The DISC*S FiberStar system with RF Return
uses Marconi's patented single- fiber,
low-power star topology. Optical Network
Units (ONU) placed within a few hundred feet
of the home provide voice telephony services
over twisted pair copper wire plus Subcarrier
Modulation (SCM) broadcast video and high-
speed Internet Protocol (IP) data services
over coaxial cable. Up to 32 homes can be
connected to each ONU, and more than 2000
subscribers can be served from a standard
DISC*S configuration.
Installing fiber closer to the user improves
the reliability of the network and the
capability for highest data throughput.
Deploying optical technology close to the
home minimizes the type of ingress noise
which has contributed to complaints from
consumers using traditional HFC shared-
bandwidth systems.
The Marconi FTTC approach reduces
construction and materials costs by using a
single network, compared with two networks
for traditional HFC (coaxial network for
video/data, separate copper network for
voice). The DISC*S FiberStar passive
network eliminates the need for active
devices such as amplifiers, and is
network-powered rather than using
distributed batteries -- these techniques
reduce potential failure points, simplify
testing and lower maintenance costs.
"A traditional HFC network is a very complex
structure, especially when voice service is
introduced over the system," noted John
Matthes, Senior Director of Strategic
Technology for Marconi Communications.
"Trunk and bridge amplifiers, internal
couplers, diplex filters and AGC modules
represent potential network failure points.
Video signal degradation and intermodulation
distortion issues can arise as a result of
non-linear components. These can develop
into significant issues as voice traffic
increases on the network. In contrast,
DISC*S FiberStar removes those HFC
problems with a simple, elegant 'Deep Fiber'
architecture."
The DISC*S FiberStar system also provides
full element management -- from the local
serving office to the customer's wall jack and
telephone handset -- and enables the MSO
to better manage network bandwidth.
Marconi is the industry leader in "Deep Fiber
Solutions(SM)" for unclogging the last-mile
communications bottleneck. More than one
million lines of DISC*S fiber-to-the-curb
capacity have been installed, in addition to
over five million lines of copper-based voice
capacity. DISC*S FiberStar is the only FTTC
access platform being commercially deployed
in volume to provide revenue-generating
voice, video and data services.
Marconi Communications (formerly RELTEC in
the US) is a wholly owned subsidiary of GEC
(GEC is not affiliated with General Electric
Company in the United States), a world
leader in smart broadband optical networks,
access equipment, switching technology for
the Internet and network integration. GEC's
recent acquisition of US-based FORE
Systems has positioned the company to be a
leading player in the new public network and
enterprise markets in addition to its
established market leadership in the carrier
and operators sphere. It has sales to more
than 140 countries, a major presence in
Europe, North America, Africa and the
Asia-Pacific Region.
DISC*S(R) and RELTEC(R) are registered
trademarks of Marconi Communications.
FiberStar(TM) is a trademark of Marconi
Communications.
Deep Fiber HFC(SM) and Deep Fiber
Solutions(SM) are service marks of Marconi
Communications.
Editor's Notes
The DISC*S FiberStar system with RF Return
consists of a Host Digital Terminal (HDT) and
an Optical Network Unit (ONU). The HDT is
located in either the Central Office (CO) or in
the neighborhood, but within 10,000 feet of
the ONU.
Downstream, POTS (plain old telephone
service) and other voice services use a 1310
nanometer (nm) optical network to transport
telephony traffic from the DISC*S Host
Digital Terminal (HDT) to the Optical Network
Unit (ONU), where the digital signal is
down-converted and rendered as 24 analog
voice lines.
Broadband RF (video and data) is typically
placed onto the video transport layer at a
Head End or Central Office (CO). Transport of
Broadband RF from the Head End/CO to the
HDT uses 1550 nm optical transmitters and
erbium doped fiber amplifiers (EDFAs).
Granular distribution of the Broadband RF is
accomplished at the HDT by using splitter
optical cross-connects (SWXs) to deliver the
Broadband RF signal in an optical format to
each ONU. Typically, between 56 and 84
ONUs can be connected. From 8 to 32 ports
of RF can be provisioned at each ONU.
Wave division multiplexing (WDM) technology
is used to multiplex the 1310 nm POTS traffic
with the 1550 nm Broadband RF signals at
the SWX (within the HDT), thus enabling a
single-fiber solution to the ONU for
converged voice, video and data services.
A WDM within the optical interface unit (OIU)
at the ONU separates the 1310 nm and 1550
nm optical signals. POTS signals are
converted to baseband telephony signals and
relegated to the 24 twisted pair punch-down
locations at the ONU. The Broadband RF is
split into SCM broadcast video and IP data
and transported via coaxial cable to the
consumer's television set-top box or cable
modem/computer, respectively, for
DOCSIS-compliant signalling applications.
Upstream transport of RF takes advantage of
the unused spectrum within the 1310 nm
optical transport. RF Return signals (5 to 42
MHz bandwidth) and POTS signals (0 to
3.088 MHz bandwidth) are multiplexed into a
common 1310 nm signal for transport back to
the HDT. Bulk transport of return bandwidth
allows communication of all RF Return signals,
regardless of modulation technique or
spectral allocation. Return path testing uses
NCTA-recommended practices.
Traditional Hybrid Fiber Coax
Requires more costly infrastructure -- two
separate networks for voice and video/data
Requires complex range of equipment
including RF amplifiers, series- connected
cables, and distributed power supplies. Each
of these represents a potential point of
network failure.
Noise/ingress interference is aggregated from
the typical 500 homes served by each node
Requires significant power
Deep Fiber HFC using DISC*S FiberStar with
RF Return
Single-fiber network for voice, video and
data (a 20-40 percent lower initial capital
investment)
RF amplifiers not required. The network is
passive after the optical-to-RF conversion.
Distributed battery power is eliminated.
Significantly reduces potential network failure
points.
Serves 8 to 32 homes per ONU.
Requires minimal power. Supports redundant
powering via batteries and separate power
feeds to each ONU for enhanced reliability.
SOURCE Marconi Communications
/CONTACT: Ron Sciepko of Marconi
Communications, 440-353-2120, or email,
ron.sciepko@marconicomms.com/
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