Frame
Type
options
are
either
Normal
or
Short.
The
Normal
64,800-bit
FEC
frame
provides
better
protection
but
introduces
more
latency
compared
to
the
Short
16,200-bit
FEC
frame.
Therefore,
the
Short
FEC
frame
type
should
be
selected
in
applications
where
latency
is
critical
and
the
longer
frame
type
should
be
used
to
optimize
protection.
Normal
Rolloff
The
Rolloff
selection
will
determine
the
shape
of
the
output
filter.
The
occupied
bandwidth
of
the
modulated
signal
is
the
symbol
rate
multiplied
by
(1+α)
where
alpha
(α)
is
the
rolloff
factor.
By
using
a
lower
alpha,
carriers
can
be
spaced
closer
together
on
a
given
transponder
or
an
increased
symbol
rate
can
be
realized
for
a
given
bandwidth.
5
10
15
20
25
30
Pilot
When
operating
in
DVB-S2,
the
Pilot
options
are
either
ON
or
OFF.
When
pilots
are
enabled,
the
total
data
throughput
is
reduced
by
approximately
3.0%.
On
Off
Rate
Priority The
Rate
Priority
control
allows
the
operator
to
designate
which
rate
will
be
kept
constant.
When
the
Symbol
Rate
is
entered
and
Rate
Priority
is
Symbol,
the
symbol
rate
is
held
constant
and
the
Interface
rate
is
calculated.
When
the
Interface
Rate
is
entered
and
Rate
Priority
is
Interface,
the
interface
rate
is
held
constant
and
the
symbol
rate
is
calculated.
Symbol
Interface
Symbol
Rate The
number
of
symbols
transmitted
per
second.
The
amount
of
data
per
symbol
is
dependant
upon
the
modulation
type,
e.g.
QPSK,
8PSK,
etc.
Range
can
be
determined
by
feature
key.
Interface
Rate
The
Interface
Rate
is
the
bit
rate
at
the
baseband
interface.
Range
can
be
determined
by
feature
key.
17
