1640 OADMLong-Haul and Ultra Long-Haul DWDM Optical

Add/Drop Multiplexer

Alcatel builds next generation networks, delivering integrated end-to-end

voice and data networking solutions to established and new carriers, as well

as enterprises and consumers worldwide. With 130,000 employees and sales

of EURO 31 billion in 2000, Alcatel operates in more than 130 countries.

For more information, visit Alcatel on the Internet: http://www.alcatel.com

1

In today’s telecom environment,

multitudes of network growth

challenges exist. Many service

providers are still transitioning from

one service to another or one

technology to another, and trying to

keep up with an increase in bandwidth

requirements. These requirements are

not just localized requirements, but

national and international as well,

therefore, distance becomes a critical

factor in designing new networks or

upgrading old ones.

The Alcatel 1640 OADM is a

next-generation, long-haul and ultra

long-haul Dense Wavelength Division

Multiplexing (DWDM) optical

networking system. It is an ideal

solution for the growing networks of

today. Its sophisticated features

maximize the existing fiber

infrastructures with the highest traffic

carrying capacity possible. With the

1640 OADM’s out-of-band forward error

correction feature, major system

redesign and the addition of costly

intermediate regeneration stations are

avoided while nearly doubling the

distance needed between in-line

amplifiers or even quadrupling the

distance between regenerators. In

addition, with the flexible modular

design of the 1640 OADM, service

providers can cost-effectively scale

their network to meet today’s demands

and tomorrow’s growth.

As a member of Alcatel’s optical

networking family, the Alcatel 1640

OADM solves key challenges for many

of today’s service providers – how to

migrate most efficiently toward all-

optical communications networks while

extending the life of legacy components

and staying ahead of the competition.

Introduction

Features and Benefits Summary

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Ultra-high Capacity, Scalabilityand OC-192 Compatibility▼ Utilizing the full spectrum of the

C and L bands as defined by the

International Telecommunications

Union’s (ITU) grid, the 1640 OADM

delivers up to 160 channels on a

single fiber pair – an unprecedented

capacity that allows for cost-effective

growth.

▼ This next-generation DWDM system

allows for the direct interface and

transport of data rates from 100 Mbps

to 10 Gbps, giving the network

ultimate flexibility.

▼ The 1640 OADM will transport up to

160 OC-192 signals, producing the

industry’s highest traffic-carrying

capacity of 1.6 TB/S.

Signal Error Detection andCorrection▼ The 1640 OADM employs Alcatel’s

Out-Of-Band Forward Error

Correction (OOB-FEC) technology -

the most advanced method of

detecting and correcting errors on

received signals and increasing span

distance between line amplifiers and

regeneration sites.

▼ OOB-FEC helps detect problems

before they affect performance.

Provides Distance, Power andFlexibility▼ Alcatel’s Raman amplification

technology allows the 1640 OADM to

extend terrestrial span distances

without adding cosly repeaters.

▼ With the 1640 OADM, output power

and channels can be added without

replacing existing amplifier modules

or redesigning the system, thus

adding resiliency to existing span

designs.

▼ The 1640 OADM’s two-stage amplifier

architecture uses advanced filtering

and gain balancing technology to

allow use of the entire C and L bands

and, as a result, expand the fiber

carrying capacity.

▼ The 1640 OADM provides a mid-stage

optical access point between

amplifier stages so added dispersion

compensation fiber and wavelength

add/drop filters will not affect output

power or span budget.

Future-proofing your Investment▼ The 1640 OADM supports both open

and embedded optical architectures

to allow for peak performance, no

matter what migration path toward

all-optical layers might be used.

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Ultra-high Capacity,Scalability and OC-192CompatibilityDemand for bandwidth continues to

increase astronomically as the

corporate and consumer appetite for

e-Business grows. Although fiber optic

technology has advanced in recent

years, the proliferation of Internet

users worldwide and the increasing

integration between customer-facing

and "back-office" systems has made

network capacity a priority. This

situation calls for a solution that uses

existing fiber infrastructure more

efficiently.

The flexibility of the 1640 OADM and its

interfaces allow for direct connections

to both data and SONET interfaces for

incremental bandwidth growth. For

example, systems using 50 GHz channel

spacing can support up to 160 channels

on a single fiber. This unprecedented

capacity allows the life of your current

infrastructure to be extended and grow

more efficiently in the future.

The 1640 OADM will be capable of

delivering 160 channels of OC-192.

That’s 1.6 TB/S of traffic-carrying

capacity – more than any other system

available.

OC-48OC-48

OC-192

OC-192

OC-48OC-48

OC-192

OC-192OC-48

OC-48OC-192

OC-192Stand-alone MUXs

DWDM Alternative

OC-48OC-48

OC-192

OC-192

OC-48OC-48

OC-192

OC-192

1640OADM

AMP

AMP

1640OADM

OC-48OC-48

OC-192

OC-192

4

Signal Error Detection andCorrectionMany of today’s DWDM systems use

In-Band Forward Error Correction

(IB-FEC) for error detection and

correction – a technique that only

marginally improves the optical signal

performance. The 1640 OADM employs

a proven alternative called Out-Of-Band

Forward Error Correction (OOB-FEC).

This advanced error detection and

correction method, pioneered by

Alcatel, transports wavelengths farther

than any other system in the industry.

How? OOB-FEC adds additional bits to

the transmitted signal, increasing the

overall bit rate. By encompassing the

original SONET signal into an FEC

“frame,” the 1640 OADM uses more

error-correcting bits which results in a

dramatic improvement of its error-

correcting capabilities. This translates

into significant performance

improvements, including:

▼ Improves the optical signal to noise

ratio by 8-9 dB

▼ Effectively removes the residual Bit

Error Rate (BER) floor

▼ Increases distance between in-line

amplifiers by 30% to 50%

▼ Quadruples the number of DWDM

channels without increasing span

budget

▼ Increases the distances between

regenerators by four to five times

Additionally, OOB-FEC detects fiber

problems before they affect

performance. The 1640 OADM monitors

the number of bits corrected.

Therefore, the amount of error-

correction being employed can be

reported, providing a clearer view of

the quality of each section. Problems

can be detected and addressed before

they materialize as bit errors on a

customer’s signal.

5

Provides Distance, Powerand FlexibilityThe 1640 OADM allows ultra long-haul

optical networks to span great

distances cost-effectively without

sacrificing power or constantly

redesigning the systems.

With its dual-stage hybrid

Erbium/Raman amplifiers, another

Alcatel-pioneered technology, the 1640

OADM achieves error-free, unrepeatered

transmission over thousands of miles.

This capability places the 1640 OADM

at the forefront of optical technologies

and offers substantial equipment and

operational savings.

First generation, single-stage optical

amplifiers span distances while

increasing system gain, but they

sacrifice power for noise improvement.

The 1640 OADM’s two-stage design

eliminates this limitation. The

first stage serves as a preamplifier to

minimize noise so the second stage can

focus on and provide maximum power

output without concern for noise.

The output power of the 1640 OADM

amplifier module is software

provisionable from +5 dBm to +17 dBm.

To deliver more power, the 1640 OADM

will allow the addition of a pump

module that boosts total power output

to between +20 dBm and +23 dBm.

With this pump module option, power

can be added without replacing existing

amplifier modules or redesigning the

system. This offers service providers a

savings on initial system costs and the

ability to only pay for power

incrementally as the system grows.

First generation, single-stage amplifiers

experience considerable power loss

when Dispersion Compensating Fibers

(DCFs) are introduced into modules to

minimize chromatic dispersion.

Overcome this obstacle with the 1640

OADM’s two-stage amplifier which

allows optical access between the first

and second stages for placement of the

DCF. As a result, the gain of the first

amplifier stage compensates for the

loss induced by the DCF. This mid-stage

application means the DCF doesn’t

affect the power output of the second

stage or the span budget.

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Furthermore, first generation amplifiers

operate in the 1545 nm – 1560 nm

wavelength region to achieve gain

flatness. This is critical to DWDM

systems with cascaded amplifiers. The

1640 OADM is designed to use the entire

C and L bands by using an advanced

filtering and gain balancing technology

to implement a larger number of

channels. Plus, it enables transport of

higher bandwidth signals and provides

greater fiber-carrying capacity through

more efficient channel spacing.

Many times, service providers don’t

need all channels of the DWDM signal

at a particular site. For example, when

collecting traffic along a route to be

aggregated at a hub site, only a small

percentage of the available wavelengths

is required. Single-stage amplifiers can

only address this issue with expensive

hardware – couplers and mux/demux

units. The 1640 OADM’s mid-stage

access offers the ability to insert

add/drop filters. Without any penalty to

the span budget, an add/drop or pass

through can be provisioned in groups of

four channels. This is not only a cost-

effective way to add or drop

wavelengths, but it means that new

services can be provided without the

usual limitations set by single-stage

DWDM equipment.

OC-192

OC-192

OC-48

13 x 29.4 dB = 1529 km

13 x 26.4 dB = 1373 km

11 x 26.3 dB = 1157 km

10 x 25 dB = 1000 kmOC-48

40λ2.5Gb

80λ2.5Gb

40λ10Gb

80λ10Gb

OC-48

OC-48

OC-192

OC-192

7

Future-proofing yourInvestmentThe ability to cost-effectively scale

optical networks is paramount as

demands constantly change. The 1640

OADM helps service providers address

a multitude of challenges, including

increasing costs, the risk of technology

obsolescence, and the need to

continually prepare for the future.

Transitioning to an all-optical network

requires balancing short-term cost

considerations with long-term

migration plans. The 1640 OADM

supports both open and embedded

optical architectures to allow for peak

performance, no matter what migration

path toward all-optical layers might be

used. It offers a variety of wavelength

adapter options, depending upon

system requirements. These can be

either low-cost modules that require

the correct frequency from the

transport equipment (embedded), or

they can be transponders capable of

converting to the desired frequency

(open). This flexibility allows you to

interface directly to IP, LAN, Frame

Relay and ATM equipment, as well as

to legacy systems.

NML/EML

1000 - 3000 km

Terrestrial and Submarine

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Exceed expectations, nowand in the futureThe 1640 OADM is the most versatile

and powerful DWDM system of its type

available today, with the most advanced

technology, service providers will

benefit from:

▼ Seamless integration into existing and

future communications networks

▼ Superior capacity and distance at a

lower overall cost

▼ Ease of maintenance, upgrades and

expansion, thereby further reducing

cost of operation

▼ Flexibility to grow as the network

expands and evolves over time

The decision to implement the 1640

OADM will have positive effects for

years to come – effects that will be

noticed within your organization and

by your customers.

The 1640 OADM is backed by Alcatel’s

long standing reputation and

experience with building end-to-end

carrier class solutions for use on land,

undersea and around the globe. Call

or visit us today at 1-800-ALCATEL or

1-800-252-2835, www.alcatel.com.

w w w. a l c a t e l . c o m

Alcatel and the Alcatel logo are registeredtrademarks of Alcatel. All other trademarks arethe property of their respective owners. Alcatelassumes no responsibility for the accuracy of theinformation presented, which is subject to changewithout notice.

© 2001 Alcatel. All rights reserved. 10821

523-0619929-001A3J, 6-20-01, Printed in USA