Comtech EF Data DMD-2050E - Manual (Page 78)

DMD2050E Universal Satellite Modem Theory of Operation
MN-DMD2050E Revision 2 3–36
involves trying different FEC and modulation combinations with Carrier-in-Carrier until an optimal
combination is found.
For optimal Carrier-in-Carrier performance, it is recommended that the two carriers have similar
symbol rate and power. This can be achieved by selecting appropriate MODCODs as shown in
following sections.
3.11.9.1 Symmetric Data Rate Link
Consider the following example:
Satellite & Transponder Galaxy 18 @ 123º W, 13K/13K
Earth Station 1 Phoenix, AZ – 4.6 m
Earth Station 2 Phoenix, AZ – 2.4 m
Data Rate 512 kbps / 512 kbps
The traditional link was based on QPSK TPC 3/4 and required 0.96 MHz of leased BW. The LST 1
summary for the traditional link is as follows:
1 LST is Intelsat’s Lease Transmission Plan Program.