Single-channel traffic node – Comtech EF Data MIDAS 4 System and Design User Manual
Page 21

System and Design Manual, Revision 2
Introduction 1–7
Single-Channel
Traffic Node
For sites requiring a single data circuit
1
, an economical solution is to use the
integrated control/traffic modems. They provide both control and traffic
characteristics, switching between the two modes on demand. In the “idle”
condition, they are tuned to the control channels, in active communication
with the MIDAS Controller.
Once a traffic connection is requested, they switch to the traffic mode,
severing the connection with the MIDAS Controller. On termination of the
traffic connection, they return to the control mode. Figure 1-2 illustrates an
SNM-1010/1010L Data/Control Modem based remote site capable of
providing a single data circuit on demand
Figure 1-2. MIDAS SNM-1010-Series Based Traffic Site
1
The SNM-1010-Series Data/Control Modem is available in 70/140 MHz IF and L-Band RF TX/RX
frequencies.