Functional Description - Comtech EF Data CDM-750 Installation And Operation Manual

CDM-750 Advanced High-Speed Trunking Modem
Introduction
•
L-Band Monitor
•
Data Interfaces:
o (2) Gigabit 10/100/1000BaseT Interfaces (standard)
o (1) Optical Gigabit Interface (optional)
o (2) Data interface slots (optional G.703 E3/T3/STS-1 [34.368/44.768/51.84 Mbps])
•
Management: Web browser, SNMP, Telnet, EIA-232/485
•
In-band (over satellite) M&C control
•
1:1 redundancy switching available
1.2

Functional Description

The CDM-750 Advanced High-Speed Trunking Modem utilizes a high performance processor
and a real-time operating system (RTOS) combined with multiple Field Programmable Gate
Arrays (FPGAs) for optimal performance. All non-volatile memory is provided by both onboard
and Compact Flash devices. Field upgrades are easily loaded via the Ethernet port; software-
based options are added to the unit via FAST (Fully Accessible System Topology) upgrade.
The CDM-750 runs on an embedded operating system and does not have moving parts for media
storage. This design provides carrier class reliability and high speed, purpose-driven processing.
The unit can be managed through multiple interfaces providing options for both in-band and out-
of-band monitor and control:
•
SNMP MIB II and Private MIB, HTTP Web-based Management
•
Telnet (CLI), Terminal Port (CLI)
•
Serial 232/485 and Front Panel control
The platform includes support for Constant Coding and Modulation (CCM) and Adaptive Coding
and Modulation (ACM) operation. ACM allows optimization of throughput under all link
conditions.
The CDM-750 supports reception and transmission of data over satellite links via two
fundamentally different types of interface – IF and data:
•
The IF interface provides a bidirectional link with the satellite via the uplink and downlink
equipment.
•
The data interface is a bidirectional path, which connects with the customer's equipment
(assumed to be the DTE) and the modem (assumed to be the DCE). Terrestrial data is
connected using up to two (2) available 10/100/100 BaseT Ethernet interfaces. Two Plug-
in Interface Cards (PIIC) slots permit factory or field installation of optional data
interfaces such as the G.703 E3/T3 PIIC.
Modem Transmit side: Transmit data from the Ethernet interface is converted for further
processing. Generic Steam Encapsulation (GSE) captures the Ethernet frames and prepares them
for DVB-S2 framing and modulation and coding. Synchronous data interfaces are mapped into
the DVB-S2 frame directly. The modulated signal is sent to the modulator output for use at either
70/140 MHz via a BNC connector or L-Band at a Type-N connector. A fixed level L-Band
1–2
Revision 1
MN-CDM750