ADAPTIVE MODULATION SCHEME FOR THE LAND MOBILE SATELLITE
CHANNEL
Tomaž
Jožef Stefan Institute, Jam
A
B
S
TR
A
C
T/ R
E
S
U
M
J
av
ov a 3
9
or n
i k
, SI- 1
,
0
G
0
or az d
0
L
j ub
K
an
d
u
s ,
S
r e č o P
l j ana, Sl ov enia, E
l e v
m
e l
ail :
tom
az . j av or nik @
ij s. si
E
This paper analyses the performance of adaptive rate modulation scheme in narrow band land mobile g
eostationary
satellite system. The satellite channel is modelled by two- state M
ood and the
other bad channel conditions. The sig
fading
corrupts the sig
Q
sig
P
S
K
nal in the g
nal ex
hibits R
ood channel state. F
nals and convolutional encoded Q
channel conditions. The coding
ayleig
P
S
K
sig
h/ L
og
ark
ov process,
normal fading
our coding
in the bad channel state,
modulation schemes,
nal with coding
rate 1/ 2
modulation schemes are selected observing
linear predictor forecasts the channel performance in the nex
where one state denotes g
or 1/ 4
,
while the R
namely uncoded 16- Q
are transmitted according
the received sig
nal streng
A
icean
M
or
to the
th indicator. The
t transmission interval. The simulation results show that the
adaptive rate system with linear prediction can be efficiently used for pedestrian speed,
while the channel variation due
to vehicle speed in city and rural environment is too fast to be accurately forecast by linear predictor.
1
.
L
I N
and
TR
O
D
U
mobile
C
TI O
N
satellite
( L
M
S
)
systems
supplement
the
terrestrial
infrastructure is poor or where terrestrial systems are cong
depends on the propag
show that the sig
mobile
ested. The q
systems
ation characteristic between mobile terminal and satellite. M
ation path between receiver and transmitter,
areas
elevation ang
shadowing
the transmitted radio sig
where the
nown as multipath fading
nal with different attenuation and delays,
],
g
ood state [ 2
area is chang
ing
]. D
ue to the
and conseq
to provide req
ists,
satellite channel. S
( C
S
I )
is desig
uired reliability of transmission. H
everal adaptive transmission techniq
M
and on the
nal and conseq
transmitted power,
uently,
the
may arrive to the receiver. The phenomena
nal shadowing
the propag
and mutlipath fading
and the complete C
have to be sent back
.
ation conditions are better and the
the
g
eometry
ned according
owever,
of
the
ues [ 6], [ 7], [ 8
to the worst channel conditions ( bad
since the channel variation,
and thus fail to ex
S
I
the transmitter
ploit the full potential of the
], [ 9] are studied recently to increase the system
channel. The channel state information
must be available at the transmitter to implement the adaptive transmission methods in practice. C
constrains of coding
nal
hen an
systems the
hput in the radio communication systems with time varying
estimated at the receiver,
]. W
nal cannot reach the
nal. I n L
movement of either mobile terminal or satellite,
and receiver are not always optimised for current channel conditions,
reliability and throug
[ 2
uently the channel characteristics as well.
I n standard communication systems the communication link
state of the channel)
system
that the land mobile satellite channel can be modelled as a finite state
hen the direct radio path between the receiver and transmitter ex
surrounding
S
S
machine with two states. The bad state represents the poor channel as a result of sig
channel is in a
terrestrial
. The total power of echoes depends on antenna characteristics of the mobile terminal and
the type of user environment. I t was shown in [ 3
W
M
mobile terminal is operating
le of the satellite. The obstacles around mobile terminal reflect the radio sig
multiple copies of transmitted sig
are k
depends on the environment,
the
nal in L
and multipath fading
receiver without reflections. The reflections cause additional delay and attenuation of the sig
distortion caused by
where
easurements of the received sig
nal in land mobile satellite channel suffers mainly from shadowing
obstacle is placed in propag
in
uality of the received sig
or only transmission mode,
S
i.e. the modulation and coding
via return channel to the transmitter. Thus,
feedback
I
can only be
scheme and
and processing
delay,
modulation schemes and the rate of channel variation determine the performance of adaptive rate
communication systems. The propag
systems it may cause sig
ation delay in terrestrial communication systems is relatively low,
nificant deg
radation of system performance,
while in satellite
but with the efficient prediction techniq
ue the
system performance can be improved.
Proc. of First International Conf. on Advanced Satellite Mobile Systems (ASMS - 2003) 10-11 July 2003, Frascati, Italy (ESA SP-541, July 2003)
I n
this
paper
we
are
g
oing
to
analyse
the
communication channel. The paper is org
narrow
band
adaptive
L
M
S
anised as follows. I n section 2
channel. The satellite system with an adaptive coding
,
system
performance
in
two- state
satellite
we introduce the narrow band two- state radio
modulation scheme is described in section 3
. F
inally in the nex
t
section the simulation results are presented and the system performance is discussed.
2
.
N
W
A
R
R
O
W
B
A
N
D
M
O
hen a mobile is moving
D
power at L
ex
M
S
E
L
F
O
R
TH
surrounding
E
L
A
N
building
D
M
O
B
I L
E
S
A
TE
L
I TE
C
H
A
N
N
E
L
s occasionally shadow the satellite. The measurements of the received
mobile terminal show that two states of channel ex
hibits shadowing
L
ists:
g
ood channel state when the sig
nal does not
and bad channel state when the satellite is not visible from the mobile terminal. A
narrowband model based on measurements was proposed in [ 3
two- state
]. I n narrowband communication systems the sig
nal
bandwidth is smaller than the coherence bandwidth of the transmission channel. This is valid for systems with data rates
up to 1M
bit/ s. The channel model proposed in [ 3
is shown in F
ig
] describes the statistical behaviour of the satellite channel. The model
. 1.
G
au
s
s
no
s
ian
is
e
(t)
X
+
fading r(t)
+
Pgb ≈ 1 / D g
+
R
ic
e
go
an
c
fading
1
+
+
h
o
m
d
anne
L
X
b
1
l
c
h
ad
R
anne
l
w
p
F
( t )
ay
l o
o
l e
igh
gno
rm
as
il te
s
g
P
gg
r
b
go
o
o
s
t a
t e
d
/
P
al
bg
P
ba
d
s t a
t e
bb
≈ 1/ D
b
fading
+
lognormal
1/
f ad
X
c
i ng
µ, σ
P( f )
c
o
G
m
p
au
s
ro
c
p
l e
s
s
p
e
s
h
ap
T
h
e
h
s ign
ib
a l
it s
f a c t o
r
n
is t r ib
r e p
d
o
b
R
t io
r e s e n
w
e r
u
y
t w
s m
d
o
b
e
s
≈
s
f r o
m
t h
s u
r r o
g,
r e p
r e s e n
t e d
t o
v
a l u
a l
e
p
e
o
b
r a n
t s
b
d
o
e c r e a s e
r m
- s t a t e
M
a r k
is s io
in
t e r v
a l
o
d
v
a l ,
o
w
d
h
o
f
u
t io
e l . T
il e
e
n
h
e
u
o
d
t h
h
e
e
h
v
t im
is
f
m
l a n
o
d
in
t h
e
c d
e t e r m
in
e s
o
a l
l in
m
o
f
w
gn
w
h
is
p
o
e n
t h
r o
e y
c e
f
p
e it h
e
b
p
a b
o
d
t h
r o
il it y
b
e r
o
R
a b
t h
il e
a s
a
e l ,
t h
n
s . T
t
e x
a n
r m
w
b
c o
b
h
e
n
e l
d
ic e
o
R
t h
t h
e
e t w
e e n
p
t h
v
e l
l e x
in
e
d
u
a y
a t
t h
c h
a n
u
d
e
c h
e l
a n
o
n
s t a t e
f
s h
a d
gn
o
e l
r e m
r m
c h
d
p
o
p
e
c e s s . W
a r e
o
f a d
f a d
o
it h
is
t h
m
w
r o
t s
a l
a t h
is
/ l o
p
s ign
e
n
t o
e l
s s ia n
e
l t ip
n
n
e f f ic ie n
t h
u
a n
a u
m
l e igh
n
G
l it u
t io
e
c h
g c o
a r ia t io
is t r ib
l e v
r
p
f a d
a m
is t s ,
a l
il it y
m
e
e r
a t
s a t e l l it e
r a t io
c h
o
o
e
s igh
l o
b
m
r e f l e c t io
e
l o
o
d
e l l e d
c h
a r ia n
e
is
o
Fig. 1. S
e ,
t h
e l
ic h
pgg ( pbb)
pgb ( pbg)
j e c t
n
in
d
s ign
e n
w
o
r a n
t o
h
e l
t s
r
e
m
b
b
f a c t o
d
e
g o
r . W
is
. T
in
h
l e f t
e d
m
2
d
y
e f f ic ie n
σ
is t r ib
h
f a c t o
c o
d
n
b
r e c e iv
c h
y
u
e . T
ic e
a n
m
n
e r
R
t
e
o
w
c is
r igh
gn
n
n
e f f ic ie n
e l
/ l o
t h
ing
x
in
s ign
d
y
c o
w
e d
e
a n
t e d
o
d
t h
n
l e v
a d
a d
t e d
a y l e igh
t r a n
d
a n
u
is t r ib
p
s h
c a n
s a t e l l it e
d
r e f l e c t io
o
tral
ian
Fig. 1. T
e x
c
in
e r
in
g c o
e l l e d
w
in
a l
y
T
s
u
in
go
f r o
m
o
t io
l t ip
d
n
d
s q
t s
l t in
a d
d
in
u
o
b
)
h
d
,
f r o
t h
e
R
e
o
a l
t
o
m
f
t h
e
R
is
d
f o
t o
a y
µ is
is t r ib
s t a t e
)
s ign
r o
e
ic e
a r a c t e r is t ic s ,
g t h
g
a d
e d
a r e
e y s
c h
s e d
( b
u
ir e c t l y
σ. T
is
o
l y
d
( b
go
r e c e iv
y
l e igh
r e s u
u
e
b
e d
a y
µ a n
e
is t r ib
ge d
R
m
h
t h
a t e d
e f f ic ie n
a s
b
e n
u
r e c e iv
e t e r s
g.
d
a in
a n
w
g h
a r a m
h
a t t e n
b
u
l e igh
m
t io
e a n
n
is
e t e r m
in
r
n
t h
a d
e
( go
e d
e x
o
d
t
)
s t a t e
t h
e
v
r e m
T
in
t h
e l o
c it y
a in
h
e
n
t h
a n
in
v
ir o
s
t h
n
e
m
t
t r a n
f
t h
it io
d
e x
o
in
ic a l
n
n
n
t y p
c o
E
s
e
t h
e
a r a m
a r e
w
h
e n
o
d
w
u
r a t io
n
in
go
M
e a n
d
u
r a t io
n
in
b
T
im
e
s h
w
in
b
h
a d
a l u
f o
t h
c it y
v
e
ir o
m
o
b
e a n
r
c [ d
a r e
o
S
t a n
c h
a n
a t t e n
d
n
e
p
d
e c t iv
m
d
e n
il e
r o
b
a b
il it ie s
pbg c a n
a n
n
f
B
o
d
a d
s t a t e ,
s t a t e ,
Dg [ m
t
e l y ,
r u
r a l
w
it h
t e r m
b
in
e
d
a n
d
e n
h
a l
c a n
v
ir o
igh
is
pgg,
pbb,
e s c r ib
n
b
b
m
e d
e
e x
e n
u
il d
r a r e l y
s h
y
p
t s
in
pgb,
b
Db [ m
o
w
u
a r d
d
e l
σ [ d
a t io
w
e v
o
o
ia t io
B
e p
e n
e a n
d
in
m
ic h
e d
.
C
it y
s
o
n
s a t e l l it e
r a t io
e t r e s ,
in
c a u
d
u
[ 2]
s e s
n
n
u
m
a r e
m
o
b
s h
r e
o
70
e r
w
w
in
D
f
n
o
s h
a d
f
p
o
o
w
w
0
b
A =
g
D
in
g -µ[ d
e r
l e v
d
o
it s
10
u
0
- 35
.4
T
m
R
.9- 0
b
in
e r e
a t io
o
a b
o
b
e n
w
r
n
l e
il e
,
r
h
v
ir o
ic h
u
m
1. T
t e r m
b
h
e r
e
in
n
m
t h
o
p
a l
e n
e
c h
f
t
a n
d
a n
n
e l
f r a m
r o
p
s h
a d
e
n
e s .
a ga t io
o
w
in
n
g
r a l
- 10
0
0
50
- 20
10
- 18
0
n
Db f o
f
n
s e v
7- 50
]
e l e v
Dg a n
5- 10
a d
n
m
l a t e d
h
]
s h
e
r e s s e d
gs ,
a d
pbg d
t h
c a l c u
]
g
M
h
a n
r e s p
r
e n
e r e
a l . T
pgb,
s t a t e
e s
c it y
h
t e r v
e
t
d
f a c t o
d
v
in
s
n
il e . T
a n
a y
e a n
ic e
b
r s e
M
R
o
e t e r
o
igh
is s io
m
go
p
s m
e
0
.3- 0
+ D
b
B
]
e l
f o
r
s h
a d
o
w
12- 15
9- 14
4
4
e d
]
T
a b
l e
1. T
y p
ic a l
p
a r a m
e t e r
v
a l u
e s
f o
r
L
M
S
n
a r r o
w
b
a n
d
s a t e l l it e
c h
a n
n
e l
e n
t
10
b
c
h
a
sta
n
d
a
n
b
el
c
te
h
d
n
n
sta
0
Received Signal Power [dB]
a
a
el
te
- 10
g
- 20
c
h
o
sta
n
o
a
- 3
0
- 4
0
0
d
n
g
el
c
te
o
h
o
a
n
sta
0. 5
d
n
el
te
1
1. 5
2
tim e [s]
Fig. 2. R
T
a d
h
e
d
t r a n
e d
s m
a f t e r
it t e d
t h
a t .
s ign
a l
s ( t )
is
m
u
e c e iv
e d
l t ip
l ie d
s ign
b
y
a l
t h
e
p
o
w
e r
f a d
in
a n
d
g c o
c h
a n
n
x
e l
e f f ic ie n
t s
s t a t e
f o
o
t a in
b
r
t h
e d
e
c it y
f r o
m
e n
t h
e
v
4
10
ir o
m
o
n
d
m
e l
a n
d
t h
e
a d
d
it iv
o
is e
is
T
h
p
e
d
r o
m
p
o
b
s h
o
il e
u
e e d
a n
d
t
R
b
o
e
m
t h
f f
f r e q
o
a n
e
1-m
o
t h
3.
T
e
h
Fo
r
t h
c h
a n
n
c h
e
e l
R
n
a t
L
L
s t a t e
r e a s o
e l . T
E
u
n
,
t h
e r
e r ,
a n
d
h
A
e
in
e n
r d
C
b
M
o
d
I T
h
r m
Y
iv
is io
e
c h
a n
t o
m
in
im
l y
t h
e
n
n
d
p
t h
u
r o
f r e q
go
L
u
e
o
c h
a n
n
e
in
a t
p
p
m
in
f
t h
e r
e l
e
o
n
o
a l
u
o
h
in
s m
c o
l o
p
t
e
e n
w
u
a l
o
f
r
h
t h
t h
t h
r d
e r
t l y
m
e
e n
D
p
p
b
c h
r e v
e n
if ie d
. T
l e r
e d
e d
n
m
e l
r o
s u
e n
p
p
t h
e
t r a n
s m
( FD
D
l e x
e r t ie s
e
a t a
a b
s y
s t e m
u
b
t
t h
is
s h
in
m
o
o
w
p
e
r o
f o
d
n
u
in
is
v
a t e d
a c k
e
s id
t o
e s t im
f e e d
o
it t e r
)
e s s e n
id
a t
r m
e
t h
u
l a t io
p
e
a t io
n
,
a n
t h
d
p
d
e
c o
p
l o
e r
v
f o
d
o
e r
in
e f f ic ie n
n
l in
k
s id
e
s m
is s io
g s c h
e m
t r a n
d
r
w
h
,
a v
e
n
e
t
o
t h
p
e
S
t o
p
e r a t io
C
b
I
e
s e n
a r a m
a n
d
n
o
c a n
t
m
p
link c
p
h
anne
link tr ans
m
is
s
s m
r
p
link tr ans
m
is
s
tim
s
u
in
f
w
d
u
e n
h
o
n
d
e
e l
e
t h
s h
e
if t
e s
h
ic h
ic e a n
t o
o
u
v
- s t a t e
t p
r a n
e
t s
t im
o
b
h
n
w
t w
ic e a n
h
o
c y
R
m
h
n
g t h
e d
m
e r . T
is
s
f il t e r
f r o
Fig. 2. T
n
u
e
a n
in
e f f ic ie n
e n
t h
R
v
e p
c e
e
c h
o
f r e q
g f r o
e n
e
m
g c o
t
it h
l o
in
y
A
ation &
ion m
ode
p
s
r e
e
le
dic
c
C
p
o
M
s y
a t e d
t h
e x
t
w
l e
m
s
is
tim
s
ation &
ion m
p
ode
s
r e
e
dic
le
c
u
t
o
c h
f
b
y
a r ia t io
igh
e r .
o
e
t r a n
t im
e r
n
s t e m
. I n
s y
l y
t h
r e c e iv
e
s m
s l o
is
a t
it t e r
s e n
t
t
is
b
a c k
tion
downlink data
u
m
is
s
u
ion
p
link tr ans
m
is
s
ion m
ode
link data
down link tr ans
m
ode
p
m
is
s
ion
ode
f
d
downlink c
tion
h
anne
downlink tr ans
tion
Fig. 3. A
C
M
s a t e l l it e
s y
s t e m
l e
m
is
s
tim
s
p
ation &
ed
ion m
ode
p
s
es
r e
e
le
t r ia
dic
c
n
tion
tion
e
v
ia
c a l c u
tion
d vehicle
l e
r
t t e d
f
m
o
g t h
t o
n
it t e d
ion
downlink data
anne
o
u
t in
e s t im
a c k
f o
ode
u
h
d
l e r
it c h
if t
c y
w
t h
o
in
p
a b
a r ia t io
a n
e
b
e t e r s
t r a n
f
b
link data
downlink tr ans
downlink tr ans
p
s e q
s h
e n
f a d
e n
o
s w
h
Fig. 3.
u
u
t ia l
a n
r e c e iv
n
u
downlink c
u
D
a r y
e igh
w
e
is
e n
c y
is
o
e
w
e f f e c t s
f il t e r e d
in
w
e
f r e q
t h
d
b
e l
p
f f
c e s s
d
e
t h
c c e s s iv
o
a r e
u
s y s t e m
e n
t o
t s
y
d
e
t
g p
h
b
o
t h
s u
a l
t
f r e q
t a in
a n
u
in
)
h
c u
e q
f a d
M
e
ic h
e f f ic ie n
d
p
o
h
C
t . W
t h
is
w
e s c r ib
a d
w
t o
o
is
( A
s l o
e e n
c y
c o
o
n
e
e t w
s l o
a l
d
b
u
e
n
e
e
l a t io
t im
b
r m
o
s it io
u
n
f il t e r s ,
o
s l igh
e q
f o
gn
d
n
f r e q
c y . I n
e r
il e
f f
t s . T
l o
t r a n
o
is s io
a s s
o
is
is
g m
r r e l a t io
w
c u
t h
t h
p
w
d
t r a n
e f f ic ie n
f il t e r
s ign
t h
c o
t
[ 2] , [ 3]
s m
s t a t e ,
e x
ic h
f r e q
e
e
n
s e r t
h
r e a s o
e l
e . A
,
g c o
d
t iv
e
w
l e r
o
a p
t h
s e d
w
t h
o
n
r e c e iv
d
,
f a d
o
t z
c y
d
a l y
n
r
D
u
e n
a n
h
o
a n
e
a d
r
g f il t e r ,
f o
t h
e
f o
n
M
a t
n
is e
s a t e l l it e
f f
in
d
t h
e
a n
ic e a n
t h
f
r e a s o
a p
a n
e r
z e r o
r
E
R
w
o
s id
a r e
a t
] ,
e r s a
o
n
s h
d
( t ) . T
T
e l
d
t
m
S
a t io
d
l o
v
f o
t h
a n
e s
y
e r
r
n
it t e r
ic t io
g [ 10
e e n
b
w
S
in
c u
l a t io
e c t r a l
ic e
e
c h
E
s p
t im
e t w
u
s m
r e d
l e igh
v
s im
t r a n
e l . Fo
f a d
d
l o
c y
n
a y
b
d
p
is
r e d
e s
is
f o
o
r
e
e l
e
R
r a n
e r
n
m
n
e
n
a l u
w
a n
l e igh
. T
p
t h
o
f il t e r e d
v
o
u
n
f o
a t
n
e
a n
l e igh
f r e q
t h
e l
a y
e l
o
h
a n
l e
w
c h
in
is
a s
T
e
a y
it a b
o
f ir s t
R
e d
A
e l . I n
n
h
n
c c e s s iv
is
( t )
s e
r e c e iv
a n
d
s u
k
t h
e
f a s t
c y
S
a n
u
s u
e
g c h
d
d
h
in
o
is
c e d
e n
M
c h
ic h
u
u
r e c e iv
C
d
t h
m
e l
a n
f a d
m
a n
e
A
h
t h
v
( t )
f
w
o
f il t e r
d
il e . T
r r e l a t e s
a r k
t h
b
e r
a y l e igh
M
a l
t r o
o
o
e r f e c t l y
in
in
f
m
p
c o
w
c u
e d
a r e
t e r m
l d
s p
s l o
e s c r ib
e r t ie s
v
s t e m
r e t u
l a t e d
ia
r e t u
s ,
e r .
r n
a t
r n
I n
A
m
C
M
e a s u
s c h
e m
b
a n
p
T
h
d
e
o
v
m
o
d
s
t s
id
a
o
s e t
f
e r
t h
L
o
M
f
c o
S
c h
t
e f f ic ie n
e f f ic ie n
a r ia t io
u
a u
w
w
e f f ic ie n
G
s t e m
e n
d
in
a n
g m
n
o
e l
a n
g m
o
d
u
l a t io
d
L
u
n
s c h
t z
[ 3]
e m
c h
e s
h
a v
n
e l
m
a n
e
t o
o
b
e
c h
d
e l ,
w
c h
a n
n
n
e l
is
o
s e n
e
s u
f o
r
t h
gge s t
e
t r a n
t w
o
s m
gr o
is s io
u
p
s
n
o
. A
f
c c o
c h
o
r d
s e n
in
g t o
c o
d
in
t h
e
c h
g m
o
d
a n
u
n
e l
l a t io
n
e s :
•
•
s y
r e m
n
o
f
16- Q
l a t io
s s ia n
n
s c h
a n
c o
t h
A
c h
t
e
d
s c h
e m
in
d
in
g m
e m
e s ,
e l
c o
r e c e iv
M
n
t
a r e
n
a m
s h
o
o
d
u
d
e d
s ign
t h
e l y
1/ 2 o
n
in
l a t io
l a t io
e . I n
w
u
n
a l
o
w
e m
e r
c a s e
r
s c h
s c h
p
e
n
o
e m
e s ,
is
f
1/ 4 c o
v
h
e n
w
c h
o
h
e r
a d
n
w
w
l o
b
e s
l u
c h
f o
r
n
e l
a n
t io
e n
n
a n
go
o
d
c o
a l
e n
n
d
c o
d
e l
is
go
b
a d
.
c h
a n
it io
n
e d
n
e l
e
P
d
c o
w
Q
o
S
a n
n
d
s u
K
d
it io
n
s . I n
gge s t
s c h
u
e m
n
t h
c o
e s . T
d
h
is
c a s e
e d
e
Q
p
P
r o
p
w
S
e
s u
K
gge s t
s c h
e r t ie s
o
e m
f
e
a
o
b
r
a n
t w
d
o
s e l e c t e d
s ign
w
id
t h
c o
d
e d
a l s
in
Fig. 4.
1
1
0
1
0
1
0
N
0
o
tran
s
. Q
P
S
K
r=
1
/ 4
Q
P
S
K
r=
1
/ 2
Q
P
S
K
1
- Q
Q
P
S
K
r=
1
/ 4
Q
P
S
K
r=
1
/ 2
Q
P
S
K
-1
1
BER
6
6
- Q
A
A
M
M
-2
1
0
1
0
1
0
Target BER
-3
-4
0
5
1
0
1
5
2
0
SNR[dB]
Fig. 4. P
V
a r io
( R
S
u
S
e t c . T
f a d
n
t h
t h
e
R
S
T
S
h
o
in
s c h
o
p
r e
r o
s im
p
S
S
e r ,
e
e
p
p
B
E
id
f
u
o
e
s m
b
n
. A
r e c e iv
e d
c o
c o
e c a u
e
l ie d
s e l e c t e d
e
f l a t
o
it t e d
c a l c u
s e d
f
p
t h
r a t e ,
e l s . I n
a p
t h
e r e
t r a n
s e l e c t
n
is
e
r
e l y
n
is s io
o
h
t h
e r r o
a n
a c h
R
w
f
t o
it
w
s m
o
s e d
b
c h
r o
ge s
o
is
io
t r a n
a p
t h
r o
a c h
e
e r t ie s
[ 9] ,
r a d
I
r a n
p
r e
r o
g t h
R
t h
r e s h
e d
o
,
b
e m
r =
l a t io
n
R
in
o
t s
n
n
e
it c h
g h
c o
s c h
n
v
o
in
g m
t h
e
l a s t
n
o
t
o
in
e
u
n
r =
t h
n
b
e t w
t a l
d
s s u
d
g m
f r o
o
in
f
d
d
u
u
m
d
u
l a t io
l a t io
B
C
n
H
p
b
it
o
u
r o
p
l a t io
o
n
G
r t io
n
s c h
e m
s c h
s c h
e m
c k
c o
a n
e m
e s
e
u
it e
c h
a n
n
a n
a l y
s is
t o
a l
s s ia n
t o
e
q
e s
io
a u
d
s u
d
r a d
r
a s is t a t ic
n
l o
l ic it y
a s is t a t ic
l im
p
u
o
o
s im
u
e
is
o
g m
it s
g q
g q
a l
g m
in
in
in
m
d
l a t e d
e . W
s ign
in
c o
s e
f a d
f r a m
d
e n
c o
ie v
e d
n
t h
n
d
s c h
t e r s e c t io
t w
e
a t
c o
s e c o
n
e e n
e f in
1/ 4
e
a l
l a t io
a c h
l in
s c is s a
e ,
d
t io
d
g
a b
e m
l u
b
e
a n
o
in
r iz o
t h
f ir s t
d
c a n
s .
s w
in
t h
c o
f
r
l a t io
f
o
n
o
u
e
E
f o
r a w
1/ 2
h
j e c t io
B
d
o
t s . T
s
d
p
o
e ,
l d
y
n
n
u
e
e
g m
t a r ge t
s u
a p
r in
t h
j e c t io
in
I
e r e
p
t h
is
c h
e
c h
s w
E
t h
u
n
c l id
r a t e
e
c h
c h
a n
e d
it t e d
d
a n
c o
s ign
,
is
g t h
e d
e a n
n
e l
a l
a l
s
s t r e n
gt h
e l a y
s p
a r a c t e r is a t io
c h
d
in
e l
h
a s e
a n
f a d
in
g r a d
t
s t r e n
c a l c u
l d
c e ,
p
s t a n
o
is t a n
f l a t
n
r e s h
s ign
d
a n
n
a s i s t a t ic
e l
in
r e c e iv
u
a c c u
q
it c h
a s :
e l ,
a n
s m
d
[ 6] ,
r e c e iv
t r a n
a n
a m
o
gt h
l a t e d
u
n
. T
f r o
t
h
d
o
f
e
m
a t t e n
io
n
t h
B
E
c h
o
d
n
a n
n
r
l d
f l a t
n
a r e
e l ,
ge n
d
a n
d
e r a t e d
s ,
e n
r
[ 11] ,
f o
a t io
o
e p
ic a t o
u
is e
r e s h
R
d
r e a d
w
e n
h
ic h
c y
o
n
Fig. 4.
t h
d
r o
S
u
t e r s e c t io
c o
p
d
in
I ,
t a in
in
S
w
c l o
a s i s t a t ic
r e c e iv
e
b
e y e
R
u
t
e r e f o
e t e r m
p
e
g q
s t a n
a t
d
c r it e r ia
[ 6] ,
h
in
c o
s
I )
r o
n
a n
o
in
e d
o
t h
v
d
in
d
S
w
t
t h
t io
K
n
,
it h
o
n
e
l u
P
e
c o
d
in
o
n
g
t a r ge t
o
a l
e n
w
t h
a b
in
n
h
e
r m
R
c o
p
o
a t io
f o
d
r
l a t io
h
N
R
is
h
s p
e n
is
n
e
c o
d
P
h
e
b
s c h
l in
Q
t . T
e s t
n
u
e d
in
S
igh
d
. T
s
s c is s a . W
f o
o
E
l d
e n
h
m
B
r e s h
t e r s e c t io
Q
e m
p
e
o
e
e
in
S
g m
K
in
e t w
t h
t r a n
e
r m
e e n
S
s m
e s
d
o
u
d
l a t io
u
R
it t e d
m
t h
e
n
T
h
,
l y
in
B
E
e
s c h
n
e m
is
u
g
n
d
a n
16- Q
is
l o
e
B
E
w
A
R
e r
t h
R
c u
e s
in
s e d
d
b
t h
M
e
,
y
e
a n
c u
r v
e s
s t a n
e n
t h
e
s e c o
p
e
s e d
e
f ir s t
a r e
S
B
p
S
in
ge n
R
h
e
m
is
c o
N
c r it e r io
j e c t io
R
d
j e c t io
r
E
r o
g. T
N
n
r o
f o
e
gin
h
ir d
t
h
a n
t h
u
t h
n
e s . T
t e r c h
t h
is
t h
c o
r v
w
c a r r ie d
s e c o
r a t io
.
n
is
c y
p
t h
l a t io
a t io
e f f ic ie n
N
c o
t e r s e c t s
o
m
f o
e c t r a l
e m
in
d
b
o
h
f
o
s t
r o
d
y
is
b
u
t h
e
u
s t
t h
l a t io
t e r s e c t io
e r
n
n
f
e e n
o
in
igh
b
s
e t w
m
t e r s e c t io
e r a t e d
o
e d
n
R
n
p
t h
o
c o
a n
in
t ,
m
p
t h
u
t h
e
n
n
e
e
t e r
4
Bandwidth efficiency [bits/symbol]
3.5
F
C
3
A
M
C
M
2.5
2
1.5
1
0.5
0
1.4
1.42
1.44
1.46
1.48
1.5
tim e [s]
Fig. 5. C
T
h
e
a n
d
p
o
w
s id
e
e n
c o
in
s t a n
a d
a p
e r
n
o
in
a c h
c o
m
b
a n
n
d
it io
n
s ,
n
d
it io
n
s . C
s c h
e n
e . N
ir o
n
e m
e .
4.
S
W
e
m
o
k
a p
d
b
p
e r f o
c h
o
e d
n
/ s ,
s
b
p
t h
e
d
e x
w
d
d
e r f o
u
w
id
t h
id
t h
a n
a p
a n
p
>
,
t h
,
t h
c e ,
b
a n
e
e f f ic ie n
it h
b
c it y
v
e h
ic l e
FC
t
M
b
a n
e
e c a u
s e
o
d
u
w
a t
d
s p
d
u
=
4
o
o
t h
o
c h
t h
o
b
e f f ic ie n
il e
a r e
e d
t r a n
it t e d
s m
E
h
e m
s y
e
w
n
e v
p
f o
t h
e
gh
it h
u
A
e x
c e e d
e d
a c h
c a n
d
M
d
w
s c h
in
o
t h
u
b
e
id
a n
n
t h
M
n
s c h
e
is
h
s t e m
e
a v
igh
u
u
s in
a n
g A
C
s y
ic h
s im
u
M
is
n
p
h
e n
M
in
e m
t h
B
M
n
a p
R
p
o
o
n
e
M
a n
t h
d
t h
e
. I n
m
o
m
c h
m
e
s im
p
it t e r
a l
c a n
iu
e
p
e
e d
s ign
r
s t e m
s o
c o
h
s m
K
R
o
e d
s y
S
E
p
e m
r e c e iv
t r a n
P
B
. T
s c h
e
e
e
m
l ie d
)
h
4- Q
in
p
in
t h
e
t a r ge t
d
a c h
a c it y
t h
e
f
( FC
a t
,
a p
o
r o
w
e m
is
n
Fig. 2. T
t h
go
e
E
c a p
l a t io
l ie d
s c h
s e d
u
in
k
a p
w
s c h
s t e m
d
t t e d
n
e
s t e m
o
l o
is
FC
is
C
t h
e r a ge
e
s y
g m
p
a t io
t o
c y
e r
in
s
a t io
il a r
A
u
e m
a t t e n
e n
d
ga in
a t t e n
s im
h
c o
e l
e l
e l
w
e d
n
M
s
s a t e l l it e
f ix
a n
e f f ic ie n
e d
s y
t h
FC
r m
ie v
e m
l e
a n
C
e
c h
e
c h
A
t h
e
c h
t h
e r f o
a c h
d
it h
t h
e
f
p
a n
is
h
o
a n
r
e n
e
b
t
C
h
e m
e r
p
M
w
. T
. W
c a s e
s c h
igh
u
FC
s t e m
gt h
-3
10
r
Fig. 5 f o
s t r e n
M
h
r o
s y
in
in
C
w
e r
r o
a l
it h
t h
n
is
A
s t e m
a p
w
R
e
s t e m
s y
o
s ign
B
c y
s a t e l l it e
s h
t a r ge t
s c h
is
l a t io
h
d
e a r
p
e n
is
u
e m
z ,
c o
a n
f
w
h
I n
h
it io
e
0
t h
l a t io
t t e d
ic l e
e r
o
b
o
E
f
u
e h
e
t r a n
s m
C
l a t io
h
d
m
m
A
u
s c h
t
c h
e
e
w
t h
h
E
t h
s c h
S
it h
N
c h
u
w
it h
r o
p
a r is o
n
t iv
e
r a t e
64 k
b
b
e
a n
n
e l
a n
n
e l
l a t io
n
FC
M
a ga t io
t o
FC
n
M
m
o
R
b
e
t h
h
o
t h
d
e
u
igh
p
e
e
u
a v
a p
it s / s ,
t e r
s im
t w
o
s e c o
e l y
r o
r o
u
u
l a t io
is
t h
m
a d
b
n
d
e r a ge
. T
h
o
s y
e
u
s c e n
p
n
S
n
a r io
s . I n
e
t h
A
s
e
w
b
c h
a n
e s t r ia n
T
128
l a t io
s t e m
e d
V
it s / s
e r e
t h
e
n
e l
a n
d
w
s p
id
t h
e e d
is
a r e a .
s t e m
e m
t h
k
l a t e d
t h
e c t iv
s t e m
e
t h
r a l
d
[ 4]
0
c o
u
in
a n
n
l e :
e
il e
R
ir o
s im
r e s p
s y
s y
h
e
w
r u
e r
s e d
w
e ,
e
e
a r io
w
l s . T
o
h
a il a b
s . W
B
t h
S
b
Fig. 7,
in
t o
a v
m
e r a ge
d
R
u
il a r
a r e
e e d
s id
l o
N
l o
e m
s y
s p
/ s
S
t h
0
a v
s c e n
M
z .
n
30
igh
M
FC
0
it t e r
l t s ,
is
is
r a t e s
ic l e
Fig. 6 a n
a n
i t s / s / H
d
10
v
t
A
o
is
t
d
e e d
R
f
a t a
r e s u
t s . A
h
g d
a n
in
s p
B
e n
c a s e
m
n
u
l o
.5
e
t h
w
in
s l o
a t
p
c a s e
t h
e
s im
,
w
e e d
n
m
s t e m
l l o
t im
w
w
n
s y
f o
s p
e h
l o
e
=
n
v
ir o
in
R b/ B
d
v
t h
il e
e
e
e
e
o
a r e
a s
e n
n
n
e
t
t h
e
t h
t h
o
k
h
e n
d
t o
e s t r ia n
r . T
e m
e .
n
d
o
e d
m
l a t e d
c y
o
e r t ie s
n
p
ic t o
/ s
s c h
p
e r f e c t l y
n
n
e l
a t
ir o
m
s c h
n
v
e t h
r o
r a t io
p
10
i t s / s / H
a n
u
r e d
s im
m
p
t
a r e
r a l
n
e l
e n
r u
t h
n
e
m
e f f ic ie n
r
m
e
is e . T
M
l in
n
b
n
a n
n
l a t io
b
l a t io
id
p
d
r
e r w
u
c h
ir o
e e d
o
f o
R b/ B
d
o
n
v
y
m
e m
m
c y
g m
it s / s . T
ic t e d
t h
R
a r a c t e r is t ic s
r
is
C
e
id
10
E
e n
r e d
s c h
e f f ic ie n
w
c h
b
r a l
e r
E
A
w
e m
e
e r a ge
B
g o
f o
e
n
1M
t h
d
r e c e iv
h
l a t io
f
C
in
in
f
s a t e l l it e
o
N
d
d
r u
e l
e
n
A
c o
d
a n
s c h
. T
a v
t h
)
o
u
t a r ge t
e n
d
d
e r
f
M
e
d
o
c t io
R
a n
n
e
u
e p
a n
a r e
l a t io
O
t iv
it s / s
c h
n
F
. D
c it y
u
d
c it y
e c t e d
d
t h
o
e r a ge
c o
b
o
a v
n
f
c y
M
it t e d
igh
o
C
e n
g m
R
t r o
d
R b/ B
e
p
o
l a t io
r m
<
t h
m
a n
o
c y
e
M
a n
m
b
r
E
e
a l
h
n
( A
is s io
s m
in
in
a d
a n
d
B
R
n
t l y ,
e l e s s ,
E
t h
t r a n
c o
e n
e
e
e
- b
f o
e
in
w
C
b
L
a r a c t e r is t ic s
1m
A
P
256 k
e f f ic ie n
A
M
t h
in
r m
f ir s t
t h
E
e
u
t h
e r t h
t s
l ie d
e m
it s / s
p
T
t h
is
n
s m
t io
a r is o
e f f ic ie n
w
t r a n
l u
p
l a t io
e l o
o
m
t h
u
f
v
s e q
id
d
b
a t a
a t
w
o
o
n
il e
n
d
B
t
d
t h
e n
S
h
w
a n
g m
e n
o
o
e v
m
Y
n
w
o
e m
v
s c h
s h
m
d
c o
l t s
b
1/ 4 c o
c o
r e s u
s
in
15d
o
y
e d
u
d
is
e
e d
ie v
e o
e
is e
t h
d
t a n
t iv
o
4
x
n
e s t
C
n
M
p
v
a n
o
p
p
u
u
w
e r
t
t
s c h
1/ 4 c o
A
gh
gh
o
e m
l u
d
in
is
c o
l im
e
t io
FC
m
p
is
n
a r is o
it e d
y
16- Q
a l
e n
M
e f f ic ie n
b
h
c y
c o
a v
is
A
d
e
n
t o
t h
e
m
M
w
e d
t h
t r a n
Q
e
P
t h
e
o
s t
it h
S
K
s a m
s m
it t e d
e
in
b
h
o
t h
igh
e r
h
B
T
e
t h
e
s c e n
b
a n
E
R
o
t a r ge t
I f
t h
r u
r a l
e
e x
p
v
r e s u
b
s . W
w
id
t h
FC
M
f
a l u
l t s
a r e a s
e c t
a r io
d
e n
t h
e
s c h
r e c e iv
c y ,
e m
e
t h
is
l o
r
e
c it y
e t t e r
p
p
a n
e r c e n
r o
p
d
r u
t a ge
a ga t io
n
f
c o
h
e
a v
a il a b
s t a t io
a n
a d
a p
t iv
r
a d
a p
e r r o
Fig. 7 d
H
o
w
c h
n
o
t h
f o
n
t
e
h
a v
a t
p
E
e
l in
o
s h
o
s ign
w
h
e x
e r f e c t
C
ic h
o
S
s e
u
r e d
a n
e
d
it io
A
n
if ic a n
t h
e
a n
t
a d
n
t h
e l
e
A
t h
s
r
p
s t e m
t h
r o
e r
t h
t h
s ign
a n
a s
s ign
s h
n
im
p
a p
t iv
o
w
e r
u
e
w
gh
B
t a r ge t
s t a t e
n
E
o
p
c c a s io
u
R
t
o
f o
r e c a s t
t
k
n
v
e
e a r
o
a l u
w
d
o
f
f
n
A
A
e
o
t h
a l l y
C
C
p
M
M
ge
v
e
ic t o
e r m
s c h
s c h
it s
e m
e m
a n
d
E
r e d
r a l
t h
e
b
e . H
e
e c o
o
w
t r a n
s m
e s
h
m
e v
e r ,
is s io
n
igh
e r
b
t h
in
o
o
f
t h
in
e
c o
s c e n
m
m
o
p
d
u
l a t io
a r is o
a r io
s
t h
igh
e r
n
e
n
s c h
t o
B
FC
E
R
e m
M
is
l o
e
w
it h
s c h
e m
e r
t h
w
e .
a n
e l
p
b
r
p
R
R
d
a v
t h
l o
d
r o
a r a m
t h
ic t e d
a n
id
w
p
p
r o
p
u
t
m
a t
u
t h
c h
h
id
o
a n
t h
e
r u
r a l
igh
e r
t h
d
r
c y
p
o
r o
e s t im
e r
a y
e
u
e r a ge
c h
a n
t t e d
in
n
a t e d
b
e l
v
a n
a r e a
a n
n
d
it io
t
d
is
in
w
id
o
w
s
f o
h
t h
c it ie s . Fo
t h
p
ir o
v
f
s
n
t h
a n
r
t h
in
a t
t h
e
c it ie s . I n
r e a s o
n
w
e
c a n
e r r o
e f f ic ie n
c y
. I n
e
a t e d
e s t im
e d
t
d
if f e r e n
e s t r ia n
s p
s y
r m
a t io
n
o
r d
c e s
e e d
n
h
u
u
s
t h
h
a t
e
p
t h
p
r o
e
t o
b
a b
a r e
f o
t h
u
e
d
o
t h
f
n
s p
d
s m
n
e
b
e t w
C
p
p
u
a r e
I
m
w
o
b
e
e s
e e d
h
r e s u
o
d
e .
t h
d
s p
t s
e e n
f
a t
S
f
d
s id
e r
s l o
o
a d
s q
t h
f
u
e
o
e
it t e r
o
t im
e e d
w
Fig. 6 a n
il it ie s
a t io
f in
e r
c a s e
n
e a n
in
t r a n
b
e
m
t t e d
e s t im
m
t h
r e a s o
l e a s t
l o
a t
e
e r
. I f
s . I n
r
l t s
. T
e o
e
s t e m
a l . T
r e s u
t h
t
s . Fo
t e r v
n
t
e n
n
c y
e
m
l e m
in
l a t io
f o
e n
M
b
e f f ic ie n
n
m
n
C
r o
in
n
ir o
A
p
u
s t a t e
if ic a n
r
o
s im
e l
id
t h
n
n
u
v
e n
is s io
e
r e a s o
s ign
n
n
s m
e n
r a l
s e r io
h
w
a t
r u
e r a t io
t r a n
a n
c it y
r
s e
a n
t h
d
p
c h
b
r
r
f o
r . T
a r ia t io
Fig. 8. N
c o
e x
ic t o
a l . Fo
f o
c a u
n
r e d
s y s t e m
e q
e l
p
m
t h
p
c y
e f f ic ie n
n
e
a v
n
r
f o
f
e r a ge
e
t h
f o
e t e r s
t s
e f f ic ie n
a ga t io
a r e
a n
gh
is
t h
e
c h
u
s t a t e
w
t ia l
d
p
d
e s s e n
t r a c k
a r e
d
a l
a t e d
a n
a n
e r f e c t
a n
t h
o
a r e a s .
b
e f f ic ie n
f o
l t s
p
n
c o
c a n
r e s u
is
s t e m
go
e r a ge
e r e s t im
B
r
s y
in
r u
s ign
E
e
is
e r a ge
e
a n
e
B
o
a v
t o
c e s
e r a ge
r e d
h
r
in
a v
c h
d
e r a ge
a v
e . T
l e d
t h
a r e
d
e
t h
e l
s id
u
if f e r e n
a v
p
d
,
n
d
a n
s
f in
a t e d
e
a n
R
e l a y
a n
e
it t e r
e
t o
w
R
E
a r e d
c h
e n
s m
d
p
e
E
B
t h
t h
l in
h
B
t r a n
m
t h
w
e r a ge
t h
o
e
s
s e d
c o
e n
e r a ge
e r e s t im
a c t
h
n
if ic a n
o
d
u
a r e
w
e
t o
w
u
v
a t
ic t o
l t s
is
v
s t e m
m
y
r e s u
a t io
I
s y
r it h
w
c e e d
c h
p
a l go
t
a t t e n
e
f
e a r
e
t h
o
s a t e l l it e
t iv
e r ,
R
il it y
a r y
n
e l
it
B
r
o
e v
a n
l im
n
a l
s y
a r e a s
t im
n
Fig. 7:
ge o
w
r a l
o
Fig. 6:
T
e d
e
e .
f o
t h
h
e f f ic ie n
il e
e r e
l t s
is
in
c r e a s e d
c a n
n
s ign
o
in
t
a l
p
r o
e x
h
u
c e d
10
p
e r l y
ib
c r e a s e d
r e d
t o
m
/ s
in
f o
it s . C
t o
60
m
t h
e
c it y
r e c a s t
o
/ s
n
s e q
in
a
t h
u
e n
n
u
a n
e
c h
t l y
m
b
d
30
a n
,
n
s o
e r
o
m
f
m
e l
/ s
in
r u
r a l
a t t e n
u
a t io
n
e
t im
t im
e
e
s l o
s l o
t s
t s
t h
h
e
B
.
T
h
C
O
e
c o
d
t r a n
m
N
o
d
u
im
T
6
p
h
.
1.
n
h
in
m
t e r v
n
r o
v
e d
b
r o
s e q
F
Y
. L
E
0
. L
r e c o
S
h
ir o
in
n
h
t l y
t h
r e
s o
e
e
N
C
t z ,
v
u
p
a r is o
s ,
t h
e
e
e
r a t e
p
h
R
N
u
is
in
s t e m
t h
h
p
s ,
b
r e d
r e d
a t
e
r e d
igh
is
m
o
f
c h
ic t e d
e r
c l o
b
e r
igh
o
n
o
B
s e
o
h
f
E
t o
a n
n
c h
a n
t h
a n
R
-2
10
t im
e
a n
d
in
in
n
v
t h
n
t
iq
c a r r ie r
e a r
a n
s l o
t s
o
u
e ,
u
c e n
p
e r l y
w
h
u
e l
n
v
a r ia t io
e l
a t t e n
t h
d
t h
v
v
a l u
e
u
n
is
a t io
t a r ge t
e
o
s . B
E
s c h
e m
ic t o
n
c h
s c h
a n
n
t r e s ,
v
v
e r a l l
in
c r e a s e d
d
is a gr e e s
n
s y
a l u
e . I f
s t e m
p
. T
t h
e r f o
h
w
e
l in
it h
t h
e
s p
e e d
r m
a n
c e
e a r
e
p
o
o
f
is
r e d
n
e ,
m
o
s ign
ic t o
w
h
b
r
ic h
il e
is
if ic a n
t l y
R
t h
il l
h
b
o
u
f
t h
e
e
a d
b
s ,
J o
j u
e
e ,
y
n
h
o
il e
s t e d
t h
l a t e d
a n
t h
r o
B
t h
n
d
e
l a n
t h
d
e
o
s
a t
m
o
f u
t u
p
u
f
t e d
n
d
t
b
o
n
h
r
b
il e
t h
n
f o
a d
a p
A
s p
C
e
m
n
o
b
t
il e
s a t e l l it e
t iv
u
e
d
n
d
e l
e x
t
in
g
FC
e
M
r u
r a l
igh
e r
t o
h
s m
is s io
e e d
a n
n
n
c o
t h
t r a n
a n
e
e
a n
s p
c h
c h
t h
. I n
d
e x
e
r
M
e e d
f a s t e r
t h
igh
f
t h
is
f o
t o
it io
o
e s t r ia n
a r ia t io
n
a p
c o
gh
e d
it io
il it y
in
u
e l
R
p
v
n
a d
n
E
e
e l
c o
a il a b
t o
u
c h
e
r
a n
e l
a v
t h
f o
c h
n
ic a l l y
e
s t e m
n
f
a n
a m
t h
s y
w
c h
s im
d
e
a r ia t io
s y s t e m
l d
is
r e c a s t s
r a t e
t h
e
o
v
e
e
f o
e m
e l
r e c a s t s
w
r
c r e a s e
e . T
w
c ie s
in
e
n
r e d
t
f o
ic h
e n
p
l a t io
c it y
t a r ge t
f r e q
d
t h
r o
is s io
if ic a n
t r a c k
e
p
e
s m
l in
g m
t h
o
t r a n
e
s ign
c a n
c a n
e
ic h
a
c o
t e c h
e r
w
e d
t h
r
h
e r . T
s t e m
e t t e r
a b
w
a p
s h
f ix
ic t o
,
p
s y
ic t io
h
e
l t s
e
c r e a s e d
is t ic a t e d
s y
t o
e . T
p
s t e m
t h
r e s u
is
e
s y
in
n
n
a l u
il it y
a y
R
s e d
l a t io
v
is ib
E
s a t e l l it e
a l y
s im
m
w
B
h
il e
a n
t a r ge t
igh
p
b
d
e
c o
t h
o
a iw
u
0
o
h
s a t e l l it e
E
k
m
a n
s a t e l l it e
o
d
R
. A
E
m
a n
E
e
e n
y
b
e
w
il e s
u
b
a d
E
b
d
e d
a l . T
e m
t h
o
l a n
e l l o
e r e
f
20
4.
a v
E
t h
t h
N
e s c r ib
b
w
I O
a r y
d
s c h
2.
3.
n
is
n
c o
R
s
a r e
o
e
S
e s
e e d
d
U
l a t io
e m
n
n
is s io
a r e a s ,
A
L
s t a t io
it io
s m
s c h
s p
C
ge o
n
d
.
Fig. 8:
5
a r e a s
a n
m
e l
a y
m
n
o
b
d
.
e
e l .
r e .
E
a ,
M
I n
t r o
. W
d
u
e r e n
ct i o
e r ,
n
A
t o
Di g
. J a h
n
,
i t a
S
a
l
M
o
b
i l e
t e l l i t e
S
C
o
m
y s t e m
m
s
u
f o
n
i ca
r
P
t i o
n
e r s o
n
a
l
h
a
n
n
W
d
B
il e y
r o
a
&
d
S
b
a
n
o
d
n
s ,
C
in
o
m
c ,
m
N
u
n
e w
Y
i ca
t i o
o
r k
n
1997.
s ,
S
p
r in
ge r ,
B
e r l in
n
a n
.
u
t z ,
D
r d
in
g,
n
P
r o
. C
y
ga n
,
M
d
s t a t is t ic s
u
c t s ,
w
. D
w
a n
w
d
ip
c h
.s h
p
o
a n
ir o
l d
n
n
,
F. D
e l
.c o
m
m
o
.
o
d
l a in
e l ,
I E
s k
E
y
E
a n
T
r a
d
n
W
. P
a p
s a
ct i o
n
k
s
e ,
o
T
n
h
V
e
l a n
d
e h
i cu
l a
m
r
o
T
b
il e
e ch
s a t e l l it e
n
o
l o
g
y ,
v
c o
o
m
l . 40
m
u
,
p
n
p
ic a t io
c h
375- 386,
n
e l -
1991.
5.
Y
.
T
6.
W
7.
A
in
o
T
J a v
e c h
J . D
U
o
n
. T
o
d
T
e ch
u
y o
k
l a t io
n
p
e ,
o
l o
g
n
e a r
a m
f e r e n
ce ,
. H
. H
n
a n
o
z o
l m
e l s ,
I E
it h
a n
,
E
,
G
.
I E
I C
E
,
T
h
e
S
i,
S
.S
a m
n
/ T
D
M
y . V
o
o
p
A
l . 47. N
e r n
. O
Q
a
. C
l
h
t e c h
u
ie m
r n
s ,
s a
i l e
e i,
/ T
u
n
b
n
a
,
o
u
n
iq
u
e
f o
r
d
igit a l
m
o
b
il e
t i o
n
c o
m
m
u
n
ic a t io
n
s " ,
P
r o
c.
I E
E
E
V
o
1994.
e h
i cu
l a
r
1989.
d
A
n
d
S
a ,
r a
t u
r e
a p
t iv
e
e l . A
A
d
A
t iv
pl i t u
c o
r e a
a p
m
O
e
d
f
e d
C
c o
d
d
m
o
e
o
m
d
m
e d
M
u
o
v
d
d
u
l a t io
.,
m
o
u
o
l a
n
p
n
n
P
e r f o
l . 18,
l a t io
,
o
f o
e n
r m
P
c e
a n
a n
. 7,
r
t e c h
p
p
r e s s
d
L
c h
t d
,
a n
n
in
g c h
y
s t e m
a n
n
e l s ,
o
e l
. 1153- 1158,
f a d
L
20
I E
d
n
e s t im
0
E
n
0
E
a t io
n
t o
o
l s
f o
r
f l a t
.
T
r a
n
s . C
- M
S
o
m
m
u
n
.,
v
o
l .
1998.
d
r a
d
u
. G
a n
M
o
. E
J o
2,
T
l if ic a t io
M
G
d
K
p
159- 164,
,
E
. 595- 60
ik
u
n
L
s m
a r s o
o
M
,
H
p
r n
iq
. P
b
l d
. 5,
in
co
a n
o
o
" L
y
l e ,
g c h
n
.
g
e b
. J . G
.
11.
l o
. W
46,
T
10
o
. J . H
f a d
9.
a ga t a ,
n
. T
K
8.
N
e ch
A
Ra
N
n
ct i o
d
o
D
s
o
S
. 4,
o
i o
. M
D
A
n
P
r in
y s t e m
p
p
d
n
r o
a p
t iv
C
o
pa
f o
a
K
r
R
m
g
a ga ,
e
m
u
t i o
. H
H
igh
. 1134- 1147,
a t e
n
C
i ca
n
C
a m
h
a
a gu
- B
o
t i o
n
n
n
c h
it - R
1998.
m
s ,
m
u
v
o
e l ,
i,
a t e
P
S
e n
y
W
n
ic a t io
l . E
m
n
S
84- B
t e c h
,
b
o
l
ir e l e s s
P
n
o
R
r e s s
a t e
D
a t a
B
. 11,
l im
a n
p
a s e d
M
r a n
o
n
t h
. 2946- 2955,
it e d
d
T
p
,
o
s m
d
L
o
u
n
d
l a t io
o
is s io
n
n
n
,
e
N
20
0
K
M
o
d
u
l a t io
n
1.
1992.
L
e v
I E
E
E
e l - C
o
T
r a
n
t r o
n
l l e d
s . o
n
A
V
d
e h
a p
i cu
t iv
l a
e
r