Adtec digital EN-30 (version 1.02.02) Manual - Manual (Page 17)

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.
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 (requires feature key)
10 (requires feature key)
15 (requires feature key)
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.