Theory of Operation
DMD50 Universal Satellite Modem
Figure 3-3. Universal Satellite Modem Functional Block Diagram
3.1.1 Front Panel
The Front Panel includes a 2 x 16 backlit LCD Display, Indicator LEDs, and a Numeric Keypad
(refer to Section 4.1).
3.1.2 Baseband Processing
The Baseband Processor performs all of the functions required for an IBS/IDR Framing Unit, a
Reed-Solomon Codec, and an E1/T1 Drop and Insert System. In addition, the Baseband
Processing Section provides for transmit clock selection and rate adaptation as well as a rate
adapter and Plesiochronous/Doppler (PD) Buffer in the receive direction. A multiplexer is also
provided for the SCT Clock Source for Loop Timing Applications. The transmit and receive paths
may be configured independently under processor control.
3-4
TM118 – Rev. 1.1