Filter
Top Products
CDM-Qx Satellite Modem Revision 5
Front Panel Operation MN/CDMQx.IOM
5–25
The FEC type takes the highest configuration priority, and the selection here
depends on what, if any, optional plug-in Codecs are installed. The choice of
FEC type then determines what demodulation types, code rates, and data rates
are available. The order of hierarchy is therefore:
FEC type ► Demodulation type ► Code Rate ► Data Rate
(Highest) (Lowest)
If the user changes a parameter within this hierarchy, the other parameters may
become invalid. In this case, the software will change those other parameters, in
order that the configuration remains valid at all times.
Example: Suppose the user has selected Viterbi + Reed-Solomon, QPSK, Rate
1/2. Now, the user changes the demodulation type from QPSK to 16-QAM. In
this case, Rate 1/2 is no longer a valid code rate, and so it will be automatically
changed to the nearest valid code rate (Rate 3/4).
Each of the configuration sub-branches will now be described in detail.
(ConfigRxFEC) – RX FEC TYPE
All possible choices are presented at all times.
If an option is not installed (either Hardware, or FAST) or valid, the
◄ ► arrow keys will force the cursor to skip past the unavailable
choice.
CASE RULES COMMENT
Vit (Viterbi) Always valid
Vit+R-S (Viterbi +Concatenated
Reed-Solomon)
Always valid
TCM+R-S (Trellis Coded
Modulation + Concatenated
Reed-Solomon)
If 8-PSK FAST is enabled Fixed at 8-PSK and
Rate 2/3
TPC (Turbo) If the TPC codec is installed
If Vit, Vit+RS, TCM+RS, or TPC is selected, the following sub-menu will be
displayed:
Rx Rs (n/k): (◄ ►, ENT)
IESS-310 network (219/201)
IMPORTANT
Rx FEC: Vit Vit+RS TCM+RS
TPC (◄ ► ENT)
IMPORTANT