Stations With 2 Demodulator Boards; Table 3-4 Output Back-Off Sspa; Figure 3-16 Link Budget Tool - Station With 2 Demodulators - ND SatCom SKYWAN IDU 7000 Manual

Outdoor Unit and Satellite Link Design
®
SkyWAN Link Budget Calculation Tool
off of solid state power amplifiers (SSPAs) are given by the table table 3-4.
Note that if the amplifier's power class is not defined by the saturation level but the 1 dB com-
pression point (like for ND Satcom RFT 5000 series), no output back-off is required for single
carrier operation.
Number of IDUs connect-
ed to one SSPA
1
2
3
4 and more
Table 3-4 Output Back-Off SSPA
If TWTA based high power amplifiers are used instead of SSPAs an additional back-off has to
be added which is defined on the summary work sheet; refer to figure 3-18. If more than one
IDU is connected to the same ODU, besides an additional back-off the power requirement for
the amplifier is multiplied by the number of IDUs.

Stations with 2 Demodulator Boards

If a station is equipped with a second demodulator board, a second entry with the same station
parameter set but a different home channel setting has to be entered. In figure 3-16 station
"Casablanca" has two demodulators, one receiving on carrier 1, the other on carrier 2:
Figure 3-16 Link Budget Tool - Station with 2 Demodulators
90
Output back-off
1.0
3
4.5
6
Network Design and Engineering Guide 2010-10-26