Spherical antenna design for satellite communications

The paper describes a project to determine and model a performance baseline for a satellite communication system concept. It is expected to improve communication capabilities while maintaining low operational cost using a newly proposed antenna system. The system will consist of a large, stationary spherical reflector fed by multiple, steerable feeds. The size of the reflector will improve signal gain and resolvability of individual signals. This paper will use a derivation of far field solutions for spherical shaped current sources. These solutions will be used to look at the interaction between current distributions on the reflector and the resulting EM field distributions. This will allow for estimation of the beam quality of the system as a function of the reflector geometry, and feed illumination. Other methods may be applied as needed to determine the feed systems. This may include ray-tracing code for reflector based systems, and numerical simulations for phased array systems.