Rigorous mathematical Method of Moments (MoMs) for analyzing various radiating spherical structures is presented in this paper by using Dyadic Green's Functions (DGFs) in conjunction with Mixed Potential Integral Equation (MPIE) formulation. With the aid of linear Rao-Wilton-Glisson (RWG) triangular basis functions and by converting spherical DGFs to Cartesian DGFs, a conformal dipole antenna in free space and over a Perfect Electric Conductor (PEC) sphere is analyzed. The characteristics of such antennas are computed by applying multilayer spherical DGFs and asymptotic approximation methods. Mutual couplings between elements of a conformal dipole antenna array in free space and over a conducting sphere are also investigated. Good agreement between the computational results obtained by the proposed methods and those obtained from commercial simulator packages shows accuracy and high convergence speed of the presented methods.
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