Comtech EF Data C5 - Manual (Page 216)

Theory of Operation C5/K1/K3 Integrated Satellite Terminal System
5-6 Rev. 0
5.3 Modulator
The modulator provides PSK modulated carriers within the 780 to 800 MHz range. The
types of modulation that encode the transmitted baseband data from the interface PCB
are:
! BPSK
! QPSK
Refer to Section 4.2.3 for a description of each modulation type.
A block diagram of the modulator is shown in Figure 5-2.
INTERFACE MUX
OPTIONAL
FRAMING UNIT
ASYNC/AUPC
OPTIONAL
REED-SOLOMON
ENCODER
MONITOR
&
CONTROL
CONVOLUTIONAL
ENCODER
DIGITAL
SIGNAL
PROCESSING
RF
MODULATOR
REFERENCE
LO
SCT
PLL
OPTIONAL
DATA
CLK
SCT
POWER LEVEL
CONTROL
LPF
OUTPUT
RF
RF LOOPBACK
OUTPUT
Figure 5-2. Modulator Block Diagram