Mocomtech CDM-QX - Manual (Page 28)

CDM-Qx/QxL Multi-Channel Satellite Modem with DoubleTalk™ Carrier-in-Carrier® Revision 7
Introduction MN/CDMQx.IOM
1–4
• A Demodulator card performs all of the signal processing functions of carrier search,
cancellation, demodulation, Forward Error Correction, the de-framer, plesiochronous/
Doppler buffer and the receive interface circuits.
• Terrestrial data interface cards can be on the modulator cards or demodulator cards.
When a modulator and demodulator are grouped together, the data interface card can be
used for full-duplex data interface. When one or up to four ports of E1 (with D&I) are
needed, the Quad E1 Data Interface Module can be installed in Slots 3 and 4.
Figure 1-2 shows a functional block diagram of the modem with either modulators and
demodulators in all four slots; and the figure also shows a modulator in Slot 1 and a demodulator in
Slot 2 along with a Quad E1 Data Interface Module in Slots 3 and 4.
Figure 1-2. CDM-Qx/QxL Open Network Satellite Modem Block Diagrams