New Functionality For CDM-570 & CDM-570L

14 Oct 2005

Software version 1.4.2 is now available for the CDM-570 and CDM-570L Satellite Modems. The release includes some useful new features for additional bandwidth efficiencies and management flexibility.

8-QAM Modulation
This new modulation type was first introduced in the CDM-600 Satellite Modem for use with our new Low-Density Parity-Check Codes (LDPC) codec. 8-QAM is now available for the CDM-570 and CDM-570L Satellite Modems to be paired with Turbo Product Coding (TPC). There are a number of advantages to using 8-QAM modulation in the Comtech modems, including:
o Acquisition and tracking of signals is permitted at noise levels 2 - 3 dB worse than is possible with 8-PSK
o Basic performance of uncoded 8-QAM has a slightly higher peak-to-average power ratio than 8-PSK
o It is inherently more immune to the effects of phase noise than 8-PSK#

Increased Symbol Rate
The maximum symbol rate has been increased from 2.5 to 3.0 Msymbols/sec. This permits many of the combinations of modulation and forward error correction to reach higher data rates, and in many cases to reach the full 5 Mbps capability of the modem. These higher data rates are still subject to the appropriate FAST option being installed in the modem. The increase in symbol rate was implemented without modification to the hardware. Consequently, there may be a small degradation in BER versus Eb/No performance for rates above 2.5 Msymbols/sec.

New Remote Control Queries
Two new remote control queries are now available on the CDM-570 and CDM-570L, Transmit Symbol Rate(TSR) and Receive Symbol Rate (RSR).

Enhanced Management
New methods of managing the CDM-570 and CDM-570L modems via the Ethernet port are now available, including Simple Network Management Protocol (SNMP), Telnet and http. These management methods were previously only available when the optional IP Module was installed.

Buffered AGC Output Voltage
Available on the rear panel of the modem, the buffered AGC output voltage has been modified. A "normal" modecan now be selected, which is compatible with all previously shipped versions, or an alternate version. The alternate version has the slope inverted, and scaled, to give a more sensitive output.

About Comtech EFData
Comtech EF Data Corp. manufactures a broad spectrum of Data and RF products for satellite communications, including Satellite Modems, Network Monitor and Control Software, TCP/IP Performance Enhancement Proxy, Converters, Solid State Power Amplifiers, Transceivers and Satellite Terminals. All products meet or exceed the standards published by Intelsat(R), Eutelsat, Insat, AsiaSat and other worldwide and regional satellite networks. Please visit www.comtechefdata.com for more information.