Comtech EF Data CDM-625, Инструкция по установке и эксплуатации

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CDM-625 Advanced Satellite Modem Revision 1
Introduction MN-0000036 (Ref MN/CDM625.IOM)
and updates can now be sent via the Internet, e-mail, or on disk. The upgrade can be performed
without opening the unit, by simply connecting the modem to the Ethernet port of a computer.
Refer to
Chapter 4. FLASH UPGRADING
for additional information.
1.3.3 Verification
The unit includes many test modes and loopbacks for rapid verification of the correct functioning
of the unit. Of particular note is the IF loopback, which permits the user to perform a quick
diagnostic test without having to disturb external cabling. During the loopback, all of the receive
configuration parameters are temporarily changed to match those of the transmit side, and an
internal RF switch connects the modulator output to the demodulator input. When normal
operation is again selected, all of the previous values are restored.
1.3.4 Data Interfaces
The CDM-625 includes, as standard, a universal data interface that eliminates the need to exchange
interface cards for different applications. The interfaces offered include:
• RS-422 (EIA530) DCE (at rates up to 14 Mbps)
• X.21 DTE and DCE (at rates up to 14 Mbps)
• V.35 DCE (at rates up to 14 Mbps)
• G.703 E1, balanced and unbalanced
• G.703 T1, balanced
• G.703 E2, unbalanced
• G.703 T2, balanced and unbalanced
• Quad E1 Drop and Insert (QDI) – up to 4 balanced E1ports
• Serial LVDS (at rates up to 25 Mbps)
• HSSI (at rates up to 25 Mbps)
• ASI
• Four-port Ethernet 10/100 BaseT switch for IP bridging
• Dual Audio, 600 Ω (produces a single 64 kbps IBS data stream)
1.4 FAST Options and Hardware Options
The CDM-625 is extremely flexible and powerful, and incorporates a large number of optional
features. Some customers may not require all of these features, and therefore, in order to permit a
lower initial cost, the modem may be purchased with only the desired features enabled. If, at a
later date, a customer wishes to upgrade the functionality of a modem, Comtech EF Data provides
a system known as FAST (
F
ully
A
ccessible
S
ystem
T
opology) that permits the purchase and
installation of options through the use of special authorization codes, entered through the front
panel, or remotely.
The base unit is equipped with Viterbi and Reed-Solomon codecs. It offers BPSK, QPSK, and
OQPSK modulation types, and data rates up to 5.0 Mbps, with all interface types. It is, however,
limited to Closed Network operation, but includes EDMAC and AUPC
.
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