Comtech EF Data SNM-1001 - Manual (Page 13)

Introduction SNM-1001 Network Control Modem
1–2 Rev. 1
Using digital signal processing techniques, it functions as the network control channel
modem for Comtech EFData’s Bandwidth-on-Demand (BOD) Multimedia Integrated
Digital Access System (MIDAS).
Features of the SNM-1001 include the following:
•
Fully integrated master control mode functionality
•
19.2 kbit/s, QPSK, 1/2 rate burst mode demodulator
•
19.2 kbit/s, QPSK, 1/2 rate continuous mode modulator
•
Operational parameters stored in EEPROM
•
50/180 MHz operation
1.2 Mode of Operation
The SNM-1001 is an integral component of the MIDAS Network Management System
(NMS), providing the control channel communication path between the NMS and the
remote nodes.
The NMS transmits commands to the remote nodes through the SNM-1001, using a
continuous, TDM, outbound carrier. The remote nodes send requests and status messages
to the NMS using the slotted ALOHA burst inbound channel. This inbound channel
technology allows multiple remote nodes to share a single inbound carrier.
A typical NMS configuration is shown in Figure 1-2. A typical network control channel
configuration is shown in Figure 1-3.