Configuring Acm In The Cdm-750 - Comtech EF Data CDM-750 Installation And Operation Manual

CDM-750 Advanced High-Speed Trunking Modem
Adaptive Coding and Modulation (ACM) Option
7.5

Configuring ACM in the CDM-750

ACM operation is a FAST option that must be ordered, then activated in the
CDM-750 High Speed Trunking Modem. If this option is not enabled in the
modem, contact your Comtech EF Data Sales Representative to upgrade the
IMPORTANT
modem to support the desired level of ACM operation.
With ACM operation enabled, Tx and Rx Symbol Rates can be set to any rate desired up to the
maximum purchased symbol rate in 1 sps steps.:
•
Symbol rate options are: 5 Msps (standard), 15, 34, 47 and 63 Msps;
•
QPSK and 8PSK operate to 63 Msps;
•
16APSK to 47 Msps;
•
32APSK to 38 Msps.
Additionally, the following modulation types are available:
•
QPSK / 8PSK (standard);
•
QPSK / 8PSK /16APSK (FAST-enabled option);
•
QPSK / 8PSK /16APSK 32APSK (FAST-enabled option).
On the next page, Table 7-6 shows the maximum satellite data rate capacity for the symbol rate
option when used in ACM mode. Actual user data rate throughput will be at least 99% of the
maximum satellite data rate capacity when running in GSE Ethernet encapsulated mode. ACM
mode is only suggested to run in Normal (64,800 bit) frames with pilots ON.
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MN-CDM750