Compare Scenarios; Optimization; Table 3-8 Scenario 2 - Carrier Coding And Bandwidth; Table 3-9 Scenario 2 - Summarized Power Requirements - ND SatCom SKYWAN IDU 7000 Manual

Outdoor Unit and Satellite Link Design
Link Budget Examples
Therefore, the modulation and coding on this carrier can be increased, leading to the following
carrier coding and bandwidth:
Star Network
Modulation
FEC
Estimated Symbol
Rate [ksps]
Table 3-8 Scenario 2 - Carrier Coding and Bandwidth
Star Network; 2.4 m An-
tenna all
Home Channel
Power requirement [W]
Amplifier power class [W]
Power equivalent band-
width [kHz]
with UPC (Home Channel)
Carrier bandwidth [kHz]
(Home Channel)
Table 3-9 Scenario 2 - Summarized Power Requirements

Compare Scenarios

Compared to the meshed network, the star network requires:
- About 1200 kHz less bandwidth on the satellite transponder.
- On the Berlin earth station a 20 W instead of a 8 W amplifier.
The transponder bandwidth saving should compensate the higher cost of the amplifier at the
Berlin station within a very short time frame, so that the star network should be for a longer op-
eration much more economical. Assumption is that there is really only negligible communica-
tion need between the remote stations.

Optimization

There is still potential room for optimization. Whereas on carrier 2 PEB and carrier bandwidth
is almost equilibrated, on carrier 1 the network still uses only 1/3 of the available transponder
power. The limitation is given by the Casablanca earth station which is located at the edge of
the satellite footprint. To compensate this disadvantage, it makes sense to install a bigger an-
tenna at this site.
104
Carrier 1
8PSK
2/3
2713
Madrid Berlin
1 1
17.2 11.9
20 20
1064 983
3256 3256
Network Design and Engineering Guide
Carrier 2
8PSK
2/3
2203
Rome
2
8.8
20
1004
2644
Total bandwidth re-
quired ( carrier spac-
ing = 1.2) [KHz]
5900
Casablanca Tunis
2 2
23.9 12.1
30 20
2047 986
2644 2644
2010-10-26