Fiberplex WDM16, User Manual

 

Introduction

 

The

 

FiberPlex

 

WDM

 

is

 

an

 

8

 

or

 

16

 

Channel

 

Wavelength

 

Division

 

Multiplexer,

 

with

 

each

 

optical

 

channel

 

brought

 

out

 

to

 

an

 

SFP

 

slot,

 

so

 

the

 

user

 

does

 

not

 

need

 

to

 

supply

 

wavelength

‐

specific

 

modules.

 

Each

 

channel

 

can

 

be

 

linked

 

via

 

fiber

 

with

 

selected

 

FiberPlex

 

FOM

 

or

 

FOI

 

fiber

 

modules,

 

FiberPlex

 

LightViper™

 

or

 

with

 

virtually

 

any

 

third

 

party

 

fiber

 

optic

 

equipment

 

with

 

data

 

rates

 

from

 

155

 

megabits

 

up

 

to

 

3

 

gigabits

 

per

 

channel,

 

for

 

a

 

possible

 

maximum

 

aggregate

 

data

 

rate

 

of

 

48

 

gigabits.

 

The

 

user

 

data

 

enters

 

and

 

leaves

 

the

 

WDM

 

via

 

16

 

SFP

 

slots

 

on

 

the

 

WDM16,

 

or

 

8

 

slots

 

on

 

the

 

WDM8A

 

and

 

WDM8B,

 

which

 

can

 

be

 

left

 

unpopulated

 

for

 

unused

 

channels,

 

or

 

populated

 

with

 

user

‐

supplied

 

MSA

‐

compliant

 

SFP

 

modules

 

that

 

are

 

appropriate

 

for

 

the

 

user’s

 

data

 

rate,

 

protocol

 

and

 

jitter

 

requirements.

 

Internally,

 

these

 

connect

 

to

 

fiber

 

optic

 

transceivers

 

which

 

are

 

tuned

 

to

 

the

 

specific

 

wavelengths

 

for

 

the

 

channels,

 

which

 

are

 

then

 

multiplexed

 

onto

 

the

 

aggregate

 

pair

 

which

 

connect

 

to

 

the

 

other

 

WDM(s)

 

in

 

the

 

link.

 

Data

 

that

 

enters

 

a

 

specific

 

channel

 

on

 

one

 

WDM

 

will

 

appear

 

on

 

the

 

corresponding

 

channel

 

on

 

the

 

other

 

WDM(s)

 

in

 

the

 

link,

 

with

 

no

 

interference

 

with

 

any

 

other

 

channels.

 

Possible

 

link

 

configurations

 

are:

 



 

WDM16

 

to

 

WDM16

 

–

 

all

 

16

 

channels

 

through

 



 

WDM8A

 

to

 

WDM8A

 

–

 

all

 

8

 

channels

 

through

 



 

WDM8B

 

to

 

WDM8B

 

–

 

all

 

8

 

channels

 

through

 

The

 

aggregate

 

fibers

 

from

 

the

 

WDM

 

units

 

exit

 

the

 

chassis

 

via

 

a

 

duplex

 

LC

 

coupler,

 

which

 

connect

 

to

 

single

 

mode

 

fiber,

 

up

 

to

  

20

 

km

 

in

 

length.

 

Since

 

this

 

is

 

an

 

aggregated

 

wideband

 

stream,

 

any

 

user

 

equipment

 

in

 

the

 

optical

 

path

 

(switches,

 

couplers,

 

etc.)

 

must

 

be

 

able

 

to

 

accommodate

 

the

 

entire

 

bandwidth

 

without

 

attenuation,

 

and

 

will

 

not

 

be

 

able

 

to

 

receive

 

or

 

decode

 

the

 

stream

 

digitally.

 

The

 

WDM

 

units

 

have

 

provision

 

for

 

two

 

(2)

 

power

 

supply

 

modules

 

for

 

redundancy

 

each

 

having

 

capacity

 

to

 

power

 

the

 

entire

 

unit.

 

An

 

AC

 

power

 

input

 

module

 

is

 

available

 

now

 

and

 

a

 

DC

 

version

 

is

 

in

 

development;

 

both

 

are

 

‘hot

 

swappable’.

 

Key

 

Features

 



 

16

 

(or

 

8)

 

Channel

 

Active

 

Wave

 

Division

 

Multiplexer

 



 

Combines

 

16

 

(or

 

8)

 

optical

 

channels

 

into

 

a

 

single

 

fiber

 

pair

 



 

Each

 

channel

 

independently

 

supports

 

data

 

rates

 

from

 

155

 

MB

 

up

 

to

 

3

 

GB

 



 

SMPTE

 

compatible

 

internal

 

fiber

 

optics,

 

video

 

optimized

 

to

 

support

 

Pathological

 

Signals

 



 

Each

 

optic

 

channel

 

can

 

independently

 

accept

 

multimode

 

or

 

single

 

mode

 

optics,

 

coax

 

connection

 

or

 

CAT5

 

using

 

flexible

 

SFP

 

modules

 



 

Fully

 

redundant,

 

hot

 

swappable

 

power

 

for

 

ultimate

 

reliability

 

 

WDM

 

Theory

 

of

 

Operation

 

Infrared

 

light

 

has

 

a

 

frequency

 

of

 

approximately

 

400

 

Terahertz

 

(400,000

 

Gigahertz).

 

That

 

is

 

about

 

125,000

 

times

 

higher

 

than

 

the

 

data

 

rate

 

of

 

a

 

typical

 

3

 

Gigabit

 

SFP,

 

which

 

means

 

a

 

large

 

proportion

 

of

 

the

 

bandwidth

 

of

 

a

 

fiber

 

optic

 

cable

 

is

 

wasted.

 

The

 

current

 

state

 

of

 

the

 

art

 

does

 

not

 

allow

 

utilizing

 

all

 

of

 

that

 

bandwidth,

 

but

 

we

 

can

 

recover

 

some

 

of

 

it

 

by

 

a

 

technique

 

called

 

“Coarse

 

Wave

 

Division

 

Multiplexing,”

 

or

 

“CWDM.”

 

Essentially,

 

it

 

is

 

the

 

simple

 

technique

 

of

 

taking

 

each

 

3

 

Gigabit

 

channel

 

and

 

using

 

it

 

to

 

modulate

 

a

 

different

 

frequency

 

in

 

that

 

400

 

Terahertz

 

bandwidth.

 

This

 

is

 

done

 

through

 

a

 

series

 

of

 

optical

 

filters

 

and

 

combiners,

 

along

 

with

 

lasers

 

and

 

photodiodes

 

tuned

 

to

 

a

 

particular

 

infrared

 

center

 

frequency.

 

Historically,

 

however,

 

optics

 

are

 

referred

 

to,

 

not

 

by

 

their

 

frequency,

 

but

 

by

 

their

 

wavelength,

 

which

 

is

 

the

 

speed

 

of

 

light

 

divided

 

by

 

the

 

frequency.

 

In

 

the

 

traditional

 

implementation

 

of

 

a

 

CWDM,

 

it

 

is

 

the

 

user’s

 

responsibility

 

to

 

provide

 

the

 

tailored

 

SFPs

 

and

 

the

 

CWDM

 

itself,

 

which

 

may

 

require

 

adapters

 

to

 

interface

 

with

 

the

 

user

 

equipment.

 

The

 

Fiberplex

 

WDM

 

line,

 

on

 

the

 

other

 

hand,

 

is

 

an

 

active

 

WDM,

 

with

 

the

 

wavelength

‐

specific

 

components

 

already

 

tested

 

and

 

configured.

 

Instead

 

of

 

a

 

wavelength

‐

specific

 

optical

 

fiber,

 

a

 

generic

 

SFP

 

electrical

 

interface

 

is

 

provided

 

for

 

each

 

channel.

 

Any

 

SFP

 

that

 

conforms

 

to

 

the

 

MSA

 

can

 

be

 

inserted,

 

even

 

copper

‐

based

 

SFPs

 

like

 

gigabit

 

Ethernet,

 

SDI,

 

HDMI

 

or

 

MADI.

 

The

 

internal

 

SFPs

 

have

 

a

 

full

 

3

 

Gigabit

 

bandwidth,

 

video

‐

optimized.

 

Generic

 

fiber

 

SFPs

 

have

 

limitations

 

in

 

passing

 

video

 

signals,

 

since

 

they

 

do

 

not

 

maintain

 

a

 

constant

 

DC

 

level.

 

The

 

video

‐

optimized

 

SFPs

 

are

 

constructed

 

to

 

better

 

handle

 

the

 

shifting

 

DC

 

levels

 

in

 

video

 

signals.