Abstract
The pressure to move upwards from the 12/14 GHz Ku-band used for satellite communications is likely to increase in the 1990's, as spectrum congestion increases. The next available exclusive satellite band after the Ku-band is the 20/30 GHz Ka-band. The Ka-band has a 3.5 GHz bandwidth allocation, which compares favourably with a 1 GHz allocation at Ku-band. There are a number of drawbacks with operation at Ka-band, principally severe fading and a lack of cheap, reliable microwave components. There is also at present, limited experience in the design and operation of satellite systems at Ka-band in Europe. The Co-operative Olympus Data Experiment (CODE) is a Ka-band point-to-multipoint Very Small Aperture Terminal (VSAT) network using the European Space Agency experimental Olympus satellite. The Satellite Research Group at the University of Surrey, as part of an international design team for the CODE system, have contributed to aspects of CODE system design and link simulation. This thesis is based on aspects of CODE systems design and link simulation that have been undertaken as part of the design process for CODE. The systems design study includes detailed link budgets for the inbound and outbound links. VSAT parameters such as antenna size, amplifier power rating and LNA noise figure are specified for various European locations. Interference and the effect of solar outages on link performance are also considered. The inbound and outbound CODE links have been modelled using the TOPSIM III and BOSS simulation packages. Phase noise has been included in the simulation models, and the simulation results have been supplemented by hardware measurements using a satellite simulator and the Olympus satellite. The link simulation studies and hardware measurements have allowed a number of critical system parameters to be identified enabling a number of recommendations to be made regarding key CODE system specifications.