Clearwire 2009 Annual Report Download - page 23

T
ec
h
no
l
og
y
B
ot
h
our mo
bil
eW
i
MAX an
d
pre-4G networ
k
s are w
i
re
l
ess IP-
b
ase
d
,Et
h
ernet p
l
at
f
orms t
h
at are a
l
so
b
u
il
t
around ortho
g
onal frequenc
y
-division multiplexin
g
, which we refer to as OFDM, and Time Division Duplex, which
we re
f
er to as TDD,
b
ot
h
o
f
w
hi
c
h
a
ll
ow us to a
dd
ress two c
h
a
ll
enges t
h
at
f
ace w
i
re
l
ess carr
i
ers, name
l
y non-
li
ne o
f
sigh
t, w
hi
c
h
we re
f
er to as NLOS, per
f
ormance an
df
requenc
y
ut
ili
zat
i
on. Our pre-4G networ
k
s,
i
n
b
ot
h
our
domestic and international markets, rel
y
on Expedience, a proprietar
y
technolo
gy
, which supports deliver
y
of an
y
IP-compat
ibl
e
b
roa
db
an
d
app
li
cat
i
ons,
i
nc
l
u
di
ng
hi
g
h
-spee
d
Internet access an
dfi
xe
d
VoIP te
l
ep
h
ony serv
i
ces.
OFDM a
ll
ows su
bdi
v
i
s
i
on o
fb
an
d
w
id
t
hi
nto mu
l
t
i
p
l
e
f
requenc
y
su
b
-carr
i
ers so t
h
at
d
ata can
b
e
di
v
id
e
d
an
d
t
ransmitted separatel
y
to ensure a hi
g
her reliabilit
y
of packet data reception at the receivin
g
end. This characteristic
of OFDM enables a 4G network to more efficiently serve subscribers in urban and suburban settings compared t
o
e
x
i
st
i
n
g
3G tec
h
no
l
o
gi
es. Un
lik
e Frequenc
y
D
i
v
i
s
i
on Dup
l
ex, w
hi
c
h
we re
f
er to as FDD, w
hi
c
h
requ
i
res pa
i
re
d
s
pectrum with
g
uard bands, TDD onl
y
requires a sin
g
le channel for downlink and uplink, makin
g
it more flexibl
e
f
or use
i
nvar
i
ous g
l
o
b
a
l
spectrum a
ll
ocat
i
ons. It a
l
so ensures comp
l
ete c
h
anne
l
rec
i
proc
i
ty
f
or
b
etter support o
f
cl
ose
dl
oop a
d
vance
d
antenna tec
h
no
l
o
gi
es
lik
eMu
l
t
i
p
l
eInMu
l
t
i
p
l
e Out an
db
eam
f
orm
i
n
g
.A
ddi
t
i
ona
lly
, TDD
allows a service provider to maximize spectrum utilization b
y
allocatin
g
up and down link resources appropriate t
o
t
he traffic pattern over a given market. Finally, we believe radio designs for TDD are typically less complex and les
s
e
xpens
i
ve to
i
mp
l
ement t
h
an FDD ra
di
os
.
R
elative to the other commerciall
y
available next
g
eneration wireless technolo
g
ies, we believe mobil
e
W
iMAX also has the followin
g
advanta
g
es:
•
Op
en Standard.
M
obile WiMAX technology is based on the 802.16e Institute of Electrical and Electronic
s
En
gi
neers, w
hi
c
h
we re
f
er to as IEEE, stan
d
ar
d
.It
i
s an open stan
d
ar
d
t
h
at
b
u
ild
so
ff
t
h
e success o
f
t
he
802.11 IEEE famil
y
of standards more commonl
y
known as Wi-Fi.
•
Time-to-Market. Mobile WiMAX has a unique head start over other 4G technologies. We do not expect
c
ommerc
i
a
l
Long-Term Evo
l
ut
i
on, w
hi
c
h
we re
f
er to as LTE, equ
i
pment to
b
ew
id
e
l
y
d
ep
l
oye
db
e
f
ore t
he
f
ourt
hq
uarter o
f
2010, at t
h
e ear
li
est
.
•
E
xpansive and Diverse Ecos
y
stem
.
T
he
g
lobal support of mobile WiMAX continues to
g
ain momentum,
n
ow with more than 500 WiMAX deployments in 146 countries, and wireless operators in Russia and India
recent
l
y announce
d
a
ddi
t
i
ona
l
comm
i
tments to
d
ep
l
oy mo
bil
eW
i
MAX networ
k
s. W
hil
et
h
e
d
ev
i
c
e
e
cos
y
stem for 2G and 3G cellular is primaril
y
focused on telecommunications, the WiMAX ecos
y
stem
e
xten
d
s
b
eyon
d
te
l
ecommun
i
cat
i
ons an
di
nc
l
u
d
es t
h
e consumer e
l
ectron
i
cs an
d
PC
i
n
d
ustr
i
es
.
R
a
d
io Access Networ
k
Com
p
onent
s
O
ur RAN covers t
h
e“
l
ast m
il
e” an
d
connects our su
b
scr
ib
ers w
i
t
h
our tower s
i
tes. Our RAN
i
s compr
i
se
d
o
f
base station transceivers and modems used b
y
our subscribers. The customer premise equipment, which we refer to
as CPE, that operates on our network is a NLOS wireless modem that connects to an
y
IP-based device, such as a
c
omputer or a W
i
-F
i
router, us
i
ng a stan
d
ar
d
Et
h
ernet connect
i
on. It
i
ss
i
mp
l
eto
i
nsta
ll
an
d
requ
i
res no serv
i
c
e
p
rovider confi
g
uration or support and no software download or installation, a subscriber onl
y
needs to connect th
e
CPE to an external
p
ower source and to their com
p
uter. In addition to the CPE, we also offer our PC card in all of ou
r
d
omest
i
c mar
k
ets
.
T
he base station allows for 3
6
0de
g
ree covera
g
eb
y
emplo
y
in
g
multiple transceivers and antennas on a sin
g
l
e
t
ower to maximize subscriber densit
y
and spectral efficienc
y
. This setup is scalable, expandable and flexible,
allowin
g
us to control costs to promote efficient expansion as our subscriber base
g
rows. Our base stations
g
enerall
y
are
l
ocate
d
on ex
i
st
i
ng commun
i
cat
i
ons towers,
b
ut can a
l
so
b
ep
l
ace
d
on roo
f
tops o
fb
u
ildi
ngs an
d
ot
h
er e
l
evate
d
locations. We
g
enerall
y
lease our tower locations from third parties.
We also use a network management system that incorporates a complete set of management tools to enable th
e
c
onfiguration, management, monitoring and reporting of all network status elements. This system provides secure
,
c
entra
li
ze
d
an
d
remote con
fig
urat
i
on o
fb
ase stat
i
ons, CPE, sw
i
tc
h
es an
d
ot
h
er networ
k
e
l
ements. T
h
es
y
stem
13