Comtech EF Data CDS-100 User Manual

Page 44

CDS-100 Diversity Switch

MN-CDS100

Modem and Switch Configuration

Revision 1

4–4

See the CDM-625A or CDM625 Advanced Satellite Modem Installation and Operation

Manual (CEFD P/N MN-CDM625A or MN-CDM625) for instructions to configure one of

the four 10/100 Ethernet ports for each modem for remote Ethernet M&C.

4.2.2 Configure Carrier-in-Carrier® for Diversity Switching

The Pre-Mapped Symbol Interface (PMSI) is associated with DoubleTalk

Carrier-in-Carrier

. It

permits the modulator in a selected unit to provide a direct copy of its output (the outbound

interferer) to the second modem. The other modem may then choose to take the PMSI signal

and use it for its own CnC reference. In diversity switching, the PMSI is an EIA-485 multi-drop

bus system where one device transmits and the other device on the multi-drop bus is configured

to receive.

If you use Carrier-in-Carrier

(CnC), you must configure the CnC control setting to Redundancy

mode using the CDM-625/A front panel menus.

Do these steps to configure the CnC control setting for CDM-625/A Diversity Switching:

Step Task

From the top-level SELECT: menu, use the ◄► arrow and ENTER keys until the PMSI control

mode screen appears:

SELECT: Configuration  CnC  PMSI-control

CnC PMSI mode: Redundancy

(Idle, Redundancy, Talk, Listen) (

)

Use the ▲ ▼ arrow keys to select Redundancy, and then press ENTER.

The two modems will now need to be connected together via use of a 1:1 PMSI cable (note that

this cable bypasses the CDS-100).

• Chapter 5. CABLES

AND

CONNECTIONS

• Appendix A. CABLE DRAWINGS