FIBER
OPTICS
ILLUSTRATED
DICTIONARY
© 2003 by CRC Press LLC
Advanced
and
Emerging
Communications
Technologies Series
Series Editor-in-Chief: Saba Zamir
The
Telecommunications
Illustrated
Dictionary,
Second
Edition,
Julie
K.
Petersen
Handbook
of
Emerging
Communications
Technologies:
The
Next
Decade,
RafaelOsso
ADSL:
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Implementation,
and
Architecture,
Charles
K.
Summers
Protocols
for
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Mostafa Hashem Sherif
Protocols
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Sherif
After
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Web-Based
Systems
and
Network
Management,
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Intranet
Performance
Management,
Komel Terplan
Multi-Domain
Communication
Management
Systems, Alex Galis
Fiber
Optics
Illustrated
Dictionary,
Julie
K.
Petersen
© 2003 by CRC Press LLC
IBER
PTICS
ILLUSTRATED
DICTIONARY
JULIE
K.
PETERSENC
CRC

PRESS
Boca Raton London New
York
Washington, D.C.
© 2003 by CRC Press LLC
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© 2003 by CRC Press LLC
Preface
About This Dictionary
The
reader might assume that the process
of
writing or using a fiber optics dictionary
is
dry
and uninteresting, but that really isn't the case. Fiber optics
is
a vibrant field, not just
in
terms
of
its
growth
and
increasing sophistication, but also
in
terms
of
the people, places,
and
details that make
up
this
challenging and rewarding industry.
Fiber optics isn't
as

specialized
as
many
people assume, either. Fiber optics
forms
the
heart
of
the
telephone industry, the nervous system
of
the
computer network industry, and the organs of
many
medical,
dental, experimental, and satellite technologies. That's part
of
the reason why this diction-
ary
is
so
big.
The
Internet, the phone system,
and
wireless satellite systems are joined at the
hip,
with fiber optics landlines often supplemented
by
satellite links and vice versa.

Fiber optics
is
attracting attention
from
many
different sectors.
In
Spring 2001, over 35,000
people
from
a wide variety
of
backgrounds attended a major international fiber optics conference.
In
spite
of
the inevitable peaks and slowdowns
in
the
commercialization
of
any
new
technology,
interest
from
professionals
is
growing and there are now thousands
of

training and certification
courses
for
people
who
want
to
design, install, operate, and maintain fiber optic systems.
The Quest for Communication by Light
The
fiber optics industry
is
very recent; most
of
the
significant developments have occurred
in
the last
60
years. The application
of
fiber
to
underlying telecommunications infrastructures became
important
in
the
1980s
and
the use

of
fiber spread
to
consumer products and local area networks
by
the
late
1990s.
The
history
of
fiber optics
is
based
upon
the
efforts
of
many multitalented, tireless inventors,
who
traded social interactions for
the
thrill
of
discovery. These pioneers were passionate in their
search for a way
to
communicate with light. Alexander Graham Bell
was
more excited about his

Photophone, a light-based telephone, than almost anything he ever invented, even though it was a
commercial failure. Bell recognized that
he
dido't have all the pieces
of
the puzzle
to
make
it a
viable technology and chose
to
move
on,
but that doesn't mean the Photophone
was
a bad idea; it
justhappened
to
be
about
80
years ahead
of
its
time.
The
earliest pioneers recognized certain potentially ground-breaking properties
of
optical
ma-

terials but weren't quite sure what made them work
and,
hence, were unable
to
fully harness their
power.
For example,
in
the
1600s,
Rasmus Bartholin thoroughly described the doubly refracting
birefringent properties
of
Iceland
spar,
a type
of
transparent calcite, but wasn't able
to
work out the
mathematics. Later, both Wollaston and Nicol recognized Iceland spar could
be
assembled into
new
forms
of
prisms with special properties
for
controlling light, but it took many generations before
scientists like Thomas

Young
began
to
unravel
the
mathematics that made this material
so
uniquely
useful and applied that knowledge
to
describing the wavelike properties
of
light.
No
sooner had
scientists become comfortable with the idea
of
light behaving
as
waves when Max Planck set the
stage,
in
1900,
for a particle theory
of
light
and
Einstein elaborated and applied
the
new

ideas
in
quantum dynamics, leading
to
our current understanding
of
the photoelectric effect.
With
the com-
ing
of
the
transistor and solid-state electronics, it
was
just a matter
of
time before smaller,
less
ex-
pensive fiber-based components could
be
constructed.
While optical science was evolving,
the
fabrication
of
pure glass was advancing
as
well. Many
optical technologies

in
communications originated
in
much the
same
way
as
tongue depressors and
penlights - doctors and dentists began using
them
to
peer down people's throats.
Scientists have long suspected that glass
and
lighthad capabilities far greaterthan anything yet
imagined,
but theyweren't sure
how
to
combine
the
two
and
still keep
the
signal within
the
lightguide.
In
terms

of
communications applications, this
was
a big road block.
The
idea
of
"bending" light isn't
new;
Colladon and Tyndall demonstrated it
in
the mid-1800s
by directing light inside
an
arc
of
water. But
the
experiment remained
an
impractical curiosity until
glass
rods
were shown
to
refract light
in
the
same
way.

Even
so,
the phenomenon
of
refraction needed
to
be
better understood before glass rods could be turned into effective fiber optic filaments.
By the middle
of
the 20th century, a
few
innovative scientists began coating glass with other
materials, following the lead
of
Nicol,
who
had
bonded together
two
pieces
of
Iceland spar with
Canada balsam
to
create the Nicol prism.
The
new prism took advantage
of
the

lower refractive
index
of
Canada balsam and the birefringent properties
of
Iceland spar
to
split a beam
of
light and
direct
one
beam out the side while
the
other continued forward. When the characteristic oflight
to
© 2003 by CRC Press LLC
refract off
lower
refractive
index
materials
was
fmally
harnessed
in
the
form
of
cladding,

fiber
op-
tics
became
a practical
reality.
From
that point
on,
the
quest
for
ideal
proportions, purer glass,
and
more
powerful,
controllable light
sources
spurred
the
industry
onto
the
next
level
of
evolution.
In
the

1950s,
the
development
of
lasers
provided
the
essential energy
source
that
finally
launched
the
optical
communications
industry.
With
fiber
optics
now
widely
deployed,
has
it
become
just another ubiquitous technology,
like
telephone
poles
and

automobiles?
Perhaps
in
some
ways
this
is
true
-
cables
for
local
area
networks
can
be
readily
purchased
on
the
Internet
and
optical
couplers
cost
only
a
few
dollars.
But that doesn't

mean
the
industry
has
reached
its
limits
or that
the
technology
is
no
longer dynamically evolving.
Fiber-based
networks
are
still
in
their
infancy
and
the
exploitation
of
the
properties
of
light
is
still

young
and
full
of
promise.
In
addition,
there
are
many
areas
of
interest
in
which
problems
of
instal-
lation
and
deployment
are
tackled
in
innovative
ways.
For
example,
the
city ofHouston

has
signed
an
agreement
to
use
ahigh-tech robot
to
navigate
the
city's
sewers
to
connect hundreds
of
premises
to
the
fiber
optic
broadband
networks
to
complete
the
"last mile" between
the
populace
and
the

fiber
backbone.
Fiber
optics
is
also
becoming
important
in
the
signage,
lighting,
and
medical industries.
Light-
weight,
inexpensive
colored
light-guides,
side-emitting
filaments,
linelights,
and
pointlights
all
have
exciting
applications
in
architecture,

interior
design,
industrial
safety,
marketing,
fine
arts,
and
crafts.
Hobbyists
are
using
fiber
filaments
to
light
scale
models
and
train
sets.
Inventive developers
have
created
fiber
optic
"fabric"
in
which
the

fiber
optic
filaments
are
bent
to
deliberately release light
at
the
joints
where
the
weft
crosses
over
the
warp.
Doctors
and
dentists
use
fiber
optics
for
imaging
and
surgery.
Wherever
light
is

needed,
there's a possibility a
fiber
optic
filament
can
provide
it.
Purpose ofthe Dictionary
It
is
the
aim
of
this
book
to
fill
a
gap
in
the
literature
on
fiber
optics.
There
is
only
one

signifi-
cant
fiber
optics
dictionary
on
the
market
and
it
was
last
published
in
1998.
Many
advances
have
occurred
since
that
time
that deserve
to
be
documented.
There
is
also
a

need
for
atext priced within
the
range
of
university
students
and
technicians
taking
their certification
training.
This
dictionary
can
meet
that
need
as
well.
Audience for the Dictionary
The
Fiber
Optics
Illustrated Dictionary
is
suitable
for
awide variety

of
beginning profession-
als
in
fiber
optics,
as
well
as
students
and
instructors.
It
will
also
be
ofinterest
to
professionals
in
other
fields
who
want
to
get
a beginning
to
intennediate introduction
to

optical
technologies.
The
book
covers
historical antecedents,
network
protocols
for
telephone
and
computer
networks,
satel-
lite
technologies,
telephone
terminology,
basic
physics
concepts,
and
units
of
measure
important
in
optics.
It
also

explains
many
math
and
light-refracting concepts through a
combination
of
words
and
pictures
so
that
concepts
that
are
hard
to
understand
at
first
are
explained
in
two
ways.
This
book
does
not
attempt

to
duplicate
the
information
in
the
FOLDOC
online
dictionary
or
the
Federal
Standards
documents.
These
dictionaries
are
readily available
and
searchable
on
the
Internet
and
are
well
documented
in
Martin
Weik's

dictionary.
Instead,
the
Fiber
Optics
Illustrated
Dictionary
takes
a current
and
comprehensive
look
at
the
fiber
optics
field
and
the
various
applica-
tions
of
fiber
optics,
rounds
out
the
picture
with

some
introductory physics
and
fusion
splicing
in-
formation,
and
presents
it
in
a
form
that
is
illustrated, cross-referenced,
and
enhanced
by
historical
biogfaphies
and
URL
addresses
for
major
not-for-profit
and
educational
sites

on
the
Web.
.
I
hope
you
enjoy
using
the
book
as
much
as
I
enjoyed
preparing it (despite
the
long
hours
and
endless
search
for
accurate
and
often elusive
information).
I
am

indebted
to
the
hard
work
and
enthusiasm
of
the
professionals
at
CRC
who
helped
bring
it
to
fruition,
including
Jerry
Papke,
who
contributed
the
original
concept,
Chris
Andreasen
and
the

proofreading
staff,
who
labored over
many
pages,
and
Jamie
Sigal,
Nora
Konopka,
and
the
folks
in
the
production
and
marketing
departments
who
all
answered
questions
and
moved
the
project
along.
Thanks also to Dawn Snider for her excellent interpretation

of
the cover.
Julie
K.
Petersen
© 2003 by CRC Press LLC
About the Author
Julie
K.
Petersen
is
atechnology consultant, author,
educator,
and
outdoor enthusiast,
and
readily
admits
to
being
a technophile. Her
whole
house
is
wired
with
computer
and
video
links,

both inside
and
out,
and
there's
rarely
a
day
when
she
isn't configuring
some
new
piece
of
equipment
to
broadcast
over
a wireless
transceiver.
Since
TRS-80 computing
days,
she's
been
tweaking
and
fixing
her

own
equipment
and
talks
about
configuring a wearable computer
to
interface directly
with
GPS
data
on
the Internet.
"The
technology
is
already
here;
it'sjust amatter ofputting
all
the
pieces together.
What
you
do
is
take
ahead-worn display that projects
an
image

on
your retina
with
a laser beam that
is
eye-safe;
such
systems
already exist.
Then
you
have
a
body-worn
GPS
sensor
with
an
interface
and
wireless
link
to
the
Internet
that
goes
through
a
geographical

server.
The
server
matches
your
GPS
coordinates
with
Web
sites that offer information
on
maps,
restaurants, nearby
movie
theaters, libraries,
schools,
etc.
You
could
have
a profile online
for
your preferences,
and
the
display would
change
as
your
location

changes.
The
process would
be
transparent,
like
a third
eye,
similar
to
the
navigational
images
a fighter pilot
sees
projected
over
the
landscape
on
the
jet'stransparent
canopy,
except
even
more
natural. I've named
it
the
G-Eye™

for
geographic
eye
or
GPS
eye.
The
image
projected
on
the
user's retina
by
the
G-Eye system
would
be
tailor-made
to
the
·viewer's preferences. It doesn't
have
to
be
a
one-way
communication either.
If
the
wearer

were
a
professional
on
the job,
like
a newscaster or research scientist,
he
or
she
could
be
wearing
sensors
with
fiber
optic faceplates
to
sense
body
changes
or
changes
in
the
surrounding environment,
pressure,
temperature, light levels, etc., that
could
be

fed
back
to
the
computer network
to
act
as
a
hands-free
'body interface'
or
a roving
human
sensing
system.
The
possibilities
are
endless.
Some
people
may
see
this
as
far-fetched,
the
idea
of

the
human
organism
as
a sort ofsensory
node
on
a
distributed network, but
young
people readily understand
and
adapt
to
concepts such
as
this,
especially
if
the
new
technology promotes
or
enhances
social interactions, which this obviously
could.
The
G-Eye would
have
been impractical a

few
years
ago.
Compact diode lasers,
sensors
that
could
respond
quickly,
and
high-bandwidth network
links
weren't yet sufficiently
developed.
The
limited
capacity of
the
network infrastructure
would
have
made
such
a
two-way
system impractical,
but
the
new
broadband fiber optic networks

have
astonishing speed and capacity, enough
to
individually outstrip
the
current collective traffic
on
the
Internet. It's
feasible
to
imagine
the
entire
human
populace interconnected through a combination ofwired
and
wireless optical
links
and
satellites.
Now
equip
the
G-Eye
with
an
optional digital
video
cam

and
microphone
and
you
have
an
integrated network
and
digital phone/videoconferencing system that travels with
you,
instead ofa
half-dozen
different, unconnected, bulky
systems.
If
there
are
interruptions
in
the
network
radio
link,
then
you
could carry a length of
fiber
optic
cable that jacks
into

the
nearest cafe
or
network
vending
machine
for
a
clean
wired
link.
Fiber
optic
cables
are
lighter and
more
robust
than
most
people
realize.
If
there's
an
emergency,
the
problem of clogged airwaves (familiar
to
traditional

cell
phone
users) could
be
alleviated
by
people having these pocket cables integrated
with
their
G-Eye
systems
as
a backup
to
wireless connections. There might even
be
an
all-optical solution
in
certain
circumstances.
Imagine
free-air
optical
transceivers
mounted
on
buildings
(like
small

satellite
receiving dishes) that people jack
into
with
optical
modems,
somewhat like a two-way infrared
remote
control. That
way,
if
you're sitting
in
a park
or
at
a sidewalk cafe,
you
could
aim
at a
transceiver
to
maintain connectivity. People
have
a tendency
to
think in terms
of
single solutions

when
often
the
best solution
is
a variety of
options.
Why
putjust
forks
in
your cutlery drawer
when
there's
room
for
knives
and
spoons
as
well?
Unfortunately, I haven't
had
time
to
build
the
G-Eye
system.
The

time
demands
ofwriting a
comprehensive dictionary
on
the subject offiber optics,
which
changes
even
as
it
is
documented,
is
considerable
and
my
spare
time
is
almost nonexistent, but I'm fascinated by
the
depth
and
breadth
ofapplications people
are
developing
for
optical

waveguides, faceplates,
and
sensors
and
I'm
sure
there
are
many
more
surprises
in
store."
The
author
lives
in
the
Pacific Northwest
and
enjoys
reading, music,
film,
strategy
games,
and
interesting
cuisine.
She
advocates

the
use
of
technology
to
enhance
the
quality oflife
and
solve
human
problems
and
especially encourages scientists
and
engineers
to
apply
technology
in
ways
that
help
reduce rather
than
extend
the
work
week.
© 2003 by CRC Press LLC

How to Use the
Fiber Optics Illustrated Dictionary
General Format There
are
two
sections
to
this reference: (1) a main alphabetical body, with
nu-
meral entries following Z
and
(2) several appendices with various charts,
an
extended section
on
ArM, a quick lookup acronym dictionary, and a timeline
of
telecommunications inventions and technologies.
Entries Dictionary entries follow a common format, with the term or phrase
in
bold-
face, followed
by
its abbreviation or acronym,
if
applicable. Pronunciation
is
included
in
cases where it

may
not be obvious. Alternate names (e.g., William
Thompsom, a.k.a. Lord Kelvin) are cross-referenced. The body
of
the entry
is
included next, with multiple definitions numbered
if
there are several mean-
ings
for
a term. Finally, where appropriate, there
are
cross-references,
RFC
list-
ings,
and
URLs included
at
the end, in that order.
Abbreviations
In
many cases, the term and
its
abbreviation are described together
so
the
reader
doesn't have

to
look
up
abbreviated references
to
understand aparticular entry;
for
example, cathode-ray
tube
will oftenbe followed by
(CRT)
and
Federal
Com-
munications Commission
by
(FCC)
so
the words and their commonly used ab-
breviations become familiar
to
the reader.
Web Addresses
Web
addresses based upon Uniform Resource Locators (URLs) are listed
for
nonprofit, not-for-profit, charitable, and educational institutions
and,
in
a

few
rare instances,
for
commercial enterprises with particular relevance
for
telecom-
munications or with substantial educational content
on
their
Web
sites. For the
most part, commercial
URLs
are
not included.
If
the address isn't listed, it can
often be guessed ( or otherwise easily located
through
Web
search engines listed
in
Appendix
D.
RFCs Request for Comments (RFC) documents
are
an
integral part
of
the Internet,

and extremely important
in
terms
of
documenting the format and evolution
of
Internet protocols and technologies. For this reason, RFC references
are
listed
with many
of
the Internet-related references and
can
be
found
in
numerous
RFC
repositories online. There
is
also a partial list
of
significant or interesting
RFC
documents listed according
to
category
in
Appendix
F.

Diagrams
and
charts Illustrations are included
as
close
to
the related defmition
as
was possible
in
the
space provided. Extensive listings
of
the various ITU-T Series Recommenda-
tions
are
included
in
almost every chapter because they are the standards upon
which most Internet technologies, telecommunications standards, and commer-
cial products are built. Charts
are
usually included on the same page
as
the re-
lated definition or the
one
following.
Bootstrap
Protocol


l-"*r1r-tP1tT1rWccTileiennttlTs's;;;~
ns
of
stori
ng
and pro-
vid'

ration information. BOOTP evolved
in
the
ARPANET
days
to
allow diskless client ma-
chines, and other machines which Inight not kno\\'
their
own
Internet
addresses~
to
discover the
IP
ad-
dress~
the
address
of
a server host, and the name

of

a file
to
be loaded into memory and executed. This
is
accolnpl1shed
in
nvo
phases: address determina-
tion and bootfile selection; and
file
transfer, typi-
cally \vith
TFTP.
This has since evolved into Dy-
namic Host Configuration Protocol (DHCP).
See
Address Resolution Protocol, Dynalnic Host Con-
figuration Protocot Reverse Address Resolution
ro
oc
~
RFC
95
l.
/>term
or
ph
rase

definition
abbreviation
or
acronym
pronunciation
cross-references
Web address (URL)
Request for Comments
reference number
© 2003 by CRC Press LLC
Contents
Alphabetical Listings 1
Numerals
1043
Appendices
1049
A.
Fiber Optics Timeline 1050
B.
Asynchronous Transfer Mode (ATM) . . . . . . . . . . . . . . 1052
C.
lTU-T Series Recommendations. . . . . . . . . . . . . . . . . . . 1055
D.
List
of
World Wide
Web
Search Engines 1056
E.
List

of
Intemet Domain Name
Extensions.
. . . . . . . . . 1057
F.
Short List
of
Request for Comments (RFC)

. . . . . . . 1059
G. National Associations 1062
H.
Dial Equivalents, Radio Alphabet, Morse Code,
Metric PrefixesNalues. . . . . . . . . . . . . . . . . . . . . . . . . . . 1066
I.
ASCII Character and Control Codes. . . . . . . . . . . . . . . . 1067
© 2003 by CRC Press LLC
a.
1.
symb.
alpha,
the
first
letter
in
the
Greek
alpha-
bet.
2.

symb.
angular
acceleration.
3.
symb.
angle,
in
geometry.
Along
with
~,
often
used
in
geometric
dia-
grams
to
designate
the
angle
of
incidence
or
refrac-
tion
or
other
angles
associated

with
light
paths.
a
1.
symb.
acceleration.
See
Acceleration
2.
symb.
anode.
See
anode.
3.
abbrev.
area.
4.
symb.
atomic
mass.
5.
abbrev.
atto
See
atto
A
1.
symb.
acoustic

velocity.
See
acoustic
velocity.
2.
symb.
ampere.
See
ampere.
3.
symb.
gain.
See
gain.
A&
Al
leads
See
AlAI.
A& BNumbers
1.
Designations
for
two
of
the
wire-
less communication service categories available
through
Inmarsat

satellite
relays.
Inmarsat
A&B
ser-
vices
are
commonly
used
for
ship-to-shore
commu-
nications.
The
InmarsatA
& B
Numbers
vary
depend-
ing
upon
the
ship
and
the
selected
satellite,
but
in-
clude

voice,
facsimile,
and
data
lines.
See
Inmarsat
for
a
chart
of
service
categories.
2.
In
mobile
radio
systems
in
general,
but
especially
cellular,
the
A
Num-
ber
is
a
designation

for
the
originating
call
point,
sig-
naling
towards
the
network,
and
the
B
Number
is
the
destination
or
answering
point.
A & B bit signaling
In
communications
networks,
control
or
status
information
about
the

communica-
tions
line
itself
may
be
interspersed
with
the
data
con-
tent
that
is
being
transmitted
through
that
line.
This
is
a
form
of
in-band
signaling.
A&Bbit
signaling
is
a

technique
of
inserting
signal
state
information
into
particular
bits
at
intervals
in
the
data
transmission,
thus
robbing
a
certain
number
of
bits
from
the
total
transmission.
For
example,
A
bits

are
used
in
voice
communications
implemented
over
Tt
superframe
(SF)
networks
to
indicate
outbound
call
signaling,
with
B
bits
as
mirrors
to
the
A
bits.
Through
bit
rob-
bing,
the

A
and
B
signal
bits
are
carried
in
each
6th
and
12th
frame,
respectively,
of
each
of
the
24
T1
subchannels.
The
types
of
supervisory
information
contained
in
these
signal

bits
is
relevant
to
switched
voice
or
switched
data
services,
including
ring,
busy,
off-hook, and
on-hook
states.
In
extended
superframe
(ESF),
A,
B,
C,
and
D
bits
may
be
robbed
from

the
6th,
12th,
18th,
and
24th
frames.
In
some
telephony
systems,
tone
signaling
is
con-
verted
to
A&B
bit
signaling
for
interoperability.
There
is
a trade-off
when
bits
are
robbed.
Since

the
available bits
are
not
all used
for
data,
the
total
throughput
is
less
when
measured
over
time.
How-
ever,
for
less
demanding
voice
communications,
for
example,
the
difference
in
speed
and

quality
of
the
signal
is
not
subjectively
apparent
to
the
listener.
Diagnostic
Tt
channel
decoders
typically
show
the
A
and
B
bit
signaling
status,
along
with
other
alann,
frame
loss,

or
error
conditions.
NewerTl
systems
based
upon
bipolar
eight-zero
sub-
stitution
(B8ZS)
don't
use
this
bit-robbing
technique.
SeeB8ZS.
A
battery
1.
A
low
voltage
battery historically
used
to
provide
current
to

filaments
or
cathode
heaters
in
electron tubes, now commonly used for small
electronic
appliances
such
as
cameras,
calculators,
pen
lights,
etc.
See
battery.
2.
A
historic
nonrechargeable
FCC-Designated Communications Frequency Blocks
Block Blk. Size Frequency
Paired Frequency
Notes
Date
A Block
30 MHz 1850-1865 MHz 1930-1945 MHz MTA Broadband PCS
1994-1995
B Block

30 MHz 1870-1885 MHz 1950-1965 MHz
MTA Broadband PCS
1994-1995
C Block
30
MHz 1895-1910 MHz
1975-1990 MHz
BTA Broadband PCS
1995-1996
D Block
10
MHz 1865-1870 MHz 1945-1950 MHz
BTA Broadband PCS
1996-1997
EBlock
10
MHz 1885-1890 MHz
1965-1970
MHz
BTA Broadband PCS 1996-1997
F Block
10
MHz
1890-1895 MHz 1970-1975 MHz
BTA Broadband PCS
1996-1997
1
© 2003 by CRC Press LLC