Comtech EF Data CDM-IP 300L - Manual (Page 30)

CDM-IP 300L IP-Centric Satellite Modem Rev. 1
CD/CDMIP300L.IOM
2
1.2 M
AJOR
A
SSEMBLIES
Assembly Description
PL/9066 Modem Card
PL/9477-1 IP Module
PL/9624-1
Or
PL/9956-1 Framer Module
Note: PL/9956-1 is
required for Payload
Compression option
1.3 S
TANDARD
F
EATURES
10/100BaseT Ethernet Interface
Static IP routing for unicast and multicast
easyConnect  Mode
Powerful network management
Web Server interface for complete product management
SNMP with public and private MIB
Telnet interface for remote product M & C
Console Port interface for local network management
Configurable serial interface (EIA-232 or RS-485) for local management
Remote software/firmware upgrade via FTP
Configuration backup and restore via FTP
Local software/firmware via console port
Data rates from 2.4 kbps to 5.0 Mbps
Symmetric as well as asymmetric operation for maximum bandwidth efficiency
Automatic Uplink Power Control (AUPC)
IGMP support for multicast
1.3.1 AUPC
An important innovation in the CDM-IP is the addition of Automatic Uplink Power
Control (AUPC). This feature enables the modem to automatically adjust its output
power to maintain the E
b
/N
o
of the remote end of the satellite link constant. This provides
protection against rain fade, a particularly severe problem with Ku-band links.
To accomplish this, the framed mode of operation must be used, and the distant end
modem constantly sends back information about the demodulator E
b
/N
o
using reserved
bytes in the overhead structure. Using the E
b
/N
o
, the local modem then adjusts its output
power, and hence, a closed-loop feedback system is created over the satellite link.