Paradise P300 - Manual (Page 161)

Each
symbol
represents
several
transmitted
bits
depending
on
the
modulation:
Et
Signal
/
noise
expressed
No
at
transmitted
bit
rate
Es
Signal
/
noise
expressed
No
at
the
symbol
rate
B
P
S
K=1T
ransmitted
bit
/
symbol
QPSK
/
OQPS
K=2T
ransmitted
bit
/
symbol
8
P
S
K=3T
ransmitted
bit
/
symbol
BPSK
-
0
d
B
QPSK
/
OQPSK
-
3
d
B
8PSK
-
4.77
dB
i i i
Es No
Et No
CE
s
NN
o
No Et
Measure:
Noise
Carrier
+
Noise
(C+N)/N
FEC
decoder
reduces
data
rate
&
corrects
errors.
Data
rate
reduced
by
FEC
code
rate:
E
D
E
Signal
/
noise
expressed
at
No
FEC
decoder
output
rate
1
/
2
Rate
=
1
Decoded
bi
t
/
2
transmitted
bits
3
/
4
Rate
=
3
Decoded
bits/
4
transmitted
bits
7
/
8
Rate
=
7
Decoded
bit
s
/
8
transmitted
bits
2
/
3
Rate
=
2
Decoded
bit
s
/
3
transmitted
bits
1
/
2
Rate
+3
dB
3
/
4
Rate
+1.25
dB
7
/
8
Rate
+0.58
dB
2
/
3
Rate
+1.76
dB
i i i i
Et No
No
ED
E
No Et
ED
E
No
Eb No
EDE
No
EDE
No
Eb No
RS
decoder
reduces
data
rate
&
corrects
errors.
Data
rate
reduced
by
RS
code
rate:
Eb
Signal
noise
expressed
at
No
composite
information
rate
Code
rate
expressed
as
(n,k,t)
(126,1
12,7)
=
1
12
Information
bits
/
126
Decoded
(219,201,9)
=
201
Information
bits
/
219
Decoded
(225,205,10)
=
205
Information
bits
/
225
Decoded
(126,1
12,7)
+0.51
dB
(219,201,9)
+0.37
dB
(225,205,10)
+0.40
dB
i i i
Bandwidth
change
due
to
framing
is
ignored
in
INTELSA
T
definition
of
Eb/No
as
Eb
refers
to
the
composite
data
rate.
op op
N C
op
C
+
N/N
op
d
B=1
0L
o
g
op
10
-1
10
10
ii
i
-
1
0
Log
(#Bits
/
Symbol)
-
1
0
Log
(FEC
Code
Rate)
-
1
0
Log
(FEC
Code
Rate)
-
1
0
Log
(RS
Code
Rate)
-1
0L
o
g
(
)
-
1
0
Log
(#Bits
/
Symbol)
=
=
==
k
k
DEMOD
FEC
DECODER
RS
DECODER
DEFRAMING
From
Satellite
Rx
Data
(C+N
)/Nd
B
Spectrum
Analyser
Carrier+Noise
Noise
Symbol Rate
T
ransmitted
Bit
Rate
FEC
Decoded
Data
Rate
Composite Information
Rate
Summary
=
Measure
V
it
/
Seq
/
TCM
/
T
urbo
DEC
DEC
DEC
DEC
n
n
DEC
to
6.5dB
5.40dB
-
3dB
(QPSK)
2.40dB
+
1.25dB
(3
/
4
Rate)
2.40dB
3.65dB
+
0.51dB
(126,1
12,7)
3.65dB
4.16dB
i
i i
i i
i
i
i i
Example
1 1
Calculate
ratio
of
Noise
power
Carrier
power
2
Es
Energy
per
symbol
C
No
Noise
power
density
N
==
Determine
Es No
3
4
5
6
3
4
5
6
op
C
+
N/N
op
10
-1
10
10
Log
10
2
Carrier
power
Noise
power
P300H
P300 Ser
ies
M
o
dem
I
n
st
al
la
ti
o
n
an
d Oper
at
in
g Han
d
b
o
o
k
Page 161
8.
12.
4
E
b
/No
E
x
p
lan
ato
ry Di
ag
ram