A novel design of a shaped reflector for the intelsat viii-a program

摘要

Consistent with plans to provide global satellite interconnectivity [1], INTELSAT authorized construction of two additional satellites known as 805 and 806. The 805 satellite provides Asia-Pacific service with an enhanced coverage over China as viewed from the 1.10.5° East orbital location while the 806 coverage includes North/South America and Western Europe as viewed from the 310° East orbital location. The design of the antenna subsystem for these satellites is driven by several unique requirements including in-orbit polarization selectivity with stringent cross-pol isolation, high edge of coverage EIRP (which drives power handling requirements) and extended bandwidth operation which complicates the design of the components. The in-orbit polarization selectability permits either dual linear or dual circular polarization, both with frequency reuse. The in-orbit 26 dB cross-pol isolation requirement imposes stringent cross-polar constraints on all four polarizations. This requirement is necessary since standard Intelsat ground stations operate with circular polarization while other current systems servicing these markets use linear polarization. At the initiation of the contract, uncertainties in the coordination of these different systems led to this dual polarization requirement [2].