Download Simplicity 5900706 Specifications

Outdoor Unit and Satellite Link Design
Link Budget Examples
Using a 3.8m antenna for the Casablanca earth station we can achieve the following modulation and coding parameters:
Star Network;
3.8 m Antenna
Casablanca
Carrier 1
Carrier 2
Modulation
8PSK
8PSK
FEC
6/7
6/7
Estimated Symbol
Rate [ksps]
2138
1736
Table 3-10
Total bandwidth required ( carrier spacing = 1.2) [KHz]
4649
Scenario 2 - Optimized Carrier Coding and Bandwidth
Star Network; 3.8 m Antenna Casablanca
Madrid
Berlin
Rome
Casablanca
Tunis
Home Channel
1
1
2
2
2
Power requirement [W]
16.7
11.6
16.3
17.7
22.6
Amplifier power class [W]
20
20
20
20
30
Power equivalent bandwidth [kHz]
with UPC (Home Channel)
1982
1831
1870
1501
1836
Carrier bandwidth [kHz]
(Home Channel)
2566
2566
2083
2083
2083
Table 3-11
Scenario 2 - Optimized Power Requirements
Conclusion
Compared to the situation with a 2.4 m antenna in Casablanca the following parameters have
changed:
- ODU hardware cost is higher because of using a bigger antenna in Casablanca.
- Amplifier cost is unchanged because the 30 W amplifier is now used in Tunis instead of
Casablanca.
- Due to higher FEC coding on both carriers the transponder bandwidth for the network is
again reduced by 1200 kHz.
- Power and bandwidth usage on the transponder is now equilibrated for both carriers.
The bandwidth saving should again compensate the higher antenna and installation cost in
Casablanca within a short time provided that the site in Casablanca allows the installation of a
3.8 m antenna.
Further carrier optimization is not possible, because we have reached on both carriers maximum modulation and FEC. Putting bigger antennas on other sites than Casablanca would reduce power classes on the earth stations, but probably not the overall ODU cost for the
network.
2010-10-26
Network Design and Engineering Guide
105