Config!Rx) - Receive - Comtech EF Data CDM-Qx Installation And Operation Manual

CDM-Qx Satellite Modem
Front Panel Operation
(Config%Tx%Txα) – TX Roll-Off (α) factor
Tx Roll-off: 20%
The default is 35%. Select 20% or 35% using the ◄ ► arrow keys, then press
5.7.1.3 (Config%Rx) - RECEIVE
The sub-branches available are:
Rx:FEC Demod Code Data Freq
Acq Descram Buf Inv Misc CnC
Select FEC, Dem, Code, Data, Frq, Acq, Descram, Buf, Inv, Misc, or CnC using the
! " arrow keys, then press
Each of these choices is described briefly in the following table:
FEC
Demod
Code
Data
Acq
On/Off
Descram
Buf
Inv
Misc
CnC
35%
(◄ ►, ENT)
ENTER
(Forward Error Correction) This submenu permits the user to select the method of FEC
used for reception (Viterbi, TPC, etc.). FEC type takes the highest configuration priority.
(Demodulation) This submenu permits the user to select the modulation type used
for reception (BPSK, QPSK, 8-PSK, etc.). The available choice of demodulation will
depend on the FEC type chosen.
(FEC Code Rate) This submenu permits the user to select the FEC Code Rate used
for reception (Rate 1/2, Rate 3/4, etc.). The available choice of Code Rate will
depend on both the FEC type and Demodulation selected.
(Data Rate) This submenu permits the user to select the receive data rate, in steps
of 1 bps. The choice of data rate will depend on the FEC type, Demodulation, and
Code Rate selected.
(Acquisition) This submenu permits the user to determine the amount of frequency
uncertainty the demodulator will search over in order to find and lock to an incoming carrier.
This submenu permits the user to control the output state of the transmit carrier.
(Descrambler) This submenu permits the user to select whether or not data
descrambling is used.
(Buffer) This submenu permits the user to select whether or not the
Plesiochronous/Doppler buffer is used, and if so, the size of that buffer.
(Inversion) This submenu permits the user to invert the sense of the received
spectrum, or to invert the sense of the received baseband data.
(Miscellaneous) This submenu will allow the user to select Eb/No Alarm Threshold
(EbNo) and Rx roll-off (alpha) factor Rxα.
®
(Carrier-in-Carrier ) This submenu allows the user to set-up the carrier-in-carrier
parameters.
5–21
. The user will then be taken to a further submenu.
Revision 6
MN/CDMQx.IOM
.
ENTER