ND SatCom SKYWAN IDU 7000, Manual

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90 Network Design and Engineering Guide 2010-10-26
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.
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
Number of IDUs connect-
ed to one SSPA Output back-off
1 1.0
2 3
3 4.5
4 and more 6